diff --git a/flutter/lib/core/router/app_router.dart b/flutter/lib/core/router/app_router.dart
index 97293c6..0dc418e 100644
--- a/flutter/lib/core/router/app_router.dart
+++ b/flutter/lib/core/router/app_router.dart
@@ -14,6 +14,7 @@ import 'package:tma_app/features/auth/presentation/pages/login_page.dart';
 import 'package:tma_app/features/diary/presentation/pages/diary_compose_page.dart';
 import 'package:tma_app/features/diary/presentation/pages/diary_page.dart';
 import 'package:tma_app/features/diary/presentation/pages/diary_settings_page.dart';
+import 'package:tma_app/features/diary/presentation/widgets/diary_join.dart';
 import 'package:tma_app/features/entry/presentation/providers/entry_provider.dart';
 import 'package:tma_app/features/home/presentation/pages/home_page.dart';
 import 'package:tma_app/features/intro/presentation/pages/intro_page.dart';
@@ -130,6 +131,11 @@ final appRouterProvider = Provider<GoRouter>((ref) {
           ),
         ],
       ),
+      GoRoute(
+        path: AppRoutes.diaryJoinScan,
+        parentNavigatorKey: rootKey,
+        pageBuilder: (context, state) => _fadePage(state, const DiaryJoinScannerPage()),
+      ),
       // 펫 명함 — 경로가 겹치므로 고정 경로(manage·new·scan…)를 :cardId 보다 먼저 둔다
       GoRoute(
         path: AppRoutes.petCardManage,
diff --git a/flutter/lib/core/router/app_routes.dart b/flutter/lib/core/router/app_routes.dart
index a855f0f..301c88e 100644
--- a/flutter/lib/core/router/app_routes.dart
+++ b/flutter/lib/core/router/app_routes.dart
@@ -53,6 +53,9 @@ abstract final class AppRoutes {
   static String diaryWrite(String id) => '/diaries/$id/write';
   static String diarySettings(String id) => '/diaries/$id/settings';
 
+  /// 공유 다이어리 참여 스캐너 — /diaries/:diaryId 와 겹치지 않게 다른 경로에 둔다
+  static const String diaryJoinScan = '/diary-invitations/scan';
+
   static const String petCardManage = '/pet-cards/manage';
   static const String petCardCreatePattern = '/pet-cards/new/:petId';
   static const String petCardDetailPattern = '/pet-cards/:cardId';
diff --git a/flutter/lib/features/diary/data/api_diary_repository.dart b/flutter/lib/features/diary/data/api_diary_repository.dart
index 9c5af27..08aa1b9 100644
--- a/flutter/lib/features/diary/data/api_diary_repository.dart
+++ b/flutter/lib/features/diary/data/api_diary_repository.dart
@@ -12,31 +12,89 @@ import 'package:tma_app/core/utils/date_format.dart';
 import 'package:tma_app/features/diary/data/diary_repository.dart';
 import 'package:tma_app/features/diary/domain/diary.dart';
 import 'package:tma_app/features/diary/domain/diary_book.dart';
+import 'package:tma_app/features/diary/domain/diary_invitation.dart';
 import 'package:tma_app/features/diary/domain/mood.dart';
+import 'package:tma_app/features/pet/domain/pet_target.dart';
 
-/// 다이어리 경로 (backend DiariesController · DiaryPostsController · DiaryCommentsController)
+/// 다이어리 경로 (backend DiariesController · DiaryPostsController · DiaryCommentsController ·
+/// DiaryInvitationsController · DiaryMembershipsController)
 const String _kDiariesPath = '/diaries';
 const String _kPostsPath = '/diary-posts';
 const String _kCommentsPath = '/diary-comments';
+const String _kInvitationsPath = '/diary-invitations';
+const String _kMembershipsPath = '/diary-memberships';
 
 /// 책장이 가득 찼을 때 서버가 주는 코드 — 앱은 null 로 받아 화면이 직접 안내한다
 const String kDiaryFullCode = 'DIARY_001';
 
-Diary diaryFromApi(Map<String, Object?> json) => Diary(
-      id: json['id']! as String,
+/// 서버의 회원 id → 앱의 사람 id (나이면 [kMeAuthorId]).
+/// 내 id 를 모르면(이전 버전에서 로그인) 모두 나로 본다 — 그때는 공유 다이어리가 없었다
+String _personId(Object? id, String? me) => me == null || id == me ? kMeAuthorId : id! as String;
+
+/// 남이면 그 사람, 나면 null — 내 글·댓글은 내 프로필로 그린다
+DiaryPerson? _author(Map<String, Object?> json, String? me) {
+  final id = _personId(json['authorId'], me);
+  if (id == kMeAuthorId) return null;
+  final author = json['author'] as Map<String, Object?>?;
+  return DiaryPerson(
+    id: id,
+    nickname: author?['nickname'] as String?,
+    photoPath: serverFileRefOrNull(author?['photoFileId'] as String?),
+  );
+}
+
+Diary diaryFromApi(Map<String, Object?> json, {String? myUserId}) {
+  final isOwner = json['isOwner'] as bool? ?? true;
+  return Diary(
+    id: json['id']! as String,
+    name: json['name']! as String,
+    targetIds: (json['targetIds'] as List?)?.whereType<String>().toList() ?? const [],
+    ribbon: colorFromHex(json['ribbon'] as String?) ?? kRibbonColors.first,
+    tint: colorFromHex(json['tint'] as String?) ?? kDiaryTints.first,
+    coverPath: serverFileRefOrNull(json['coverFileId'] as String?),
+    mutedNotices: {
+      for (final n in (json['mutedNotices'] as List?)?.whereType<String>() ?? const <String>[])
+        ?DiaryNotice.values.where((v) => v.name == n).firstOrNull,
+    },
+    shared: json['shared'] as bool? ?? false,
+    isOwner: isOwner,
+    inviteCode: json['inviteCode'] as String?,
+    members: [
+      for (final m in (json['members'] as List?)?.whereType<Map<String, Object?>>() ?? const <Map<String, Object?>>[])
+        DiaryMember(
+          id: _personId(m['userId'], myUserId),
+          nickname: m['nickname'] as String?,
+          photoPath: serverFileRefOrNull(m['photoFileId'] as String?),
+          isOwner: m['isOwner'] as bool? ?? false,
+        ),
+    ],
+    // 내 다이어리는 내 반려동물 목록으로 그리므로 다른 사람의 다이어리일 때만 담는다
+    targets: isOwner
+        ? const []
+        : [
+            for (final t in (json['targets'] as List?)?.whereType<Map<String, Object?>>() ?? const <Map<String, Object?>>[])
+              DiaryTarget(
+                id: t['id']! as String,
+                name: t['name'] as String?,
+                photoPath: serverFileRefOrNull(t['photoFileId'] as String?),
+                isSelf: t['id'] == kSelfTargetId,
+              ),
+          ],
+  );
+}
+
+DiaryInvitation diaryInvitationFromApi(String code, Map<String, Object?> json) => DiaryInvitation(
+      code: code,
+      diaryId: json['diaryId']! as String,
       name: json['name']! as String,
-      targetIds: (json['targetIds'] as List?)?.whereType<String>().toList() ?? const [],
-      ribbon: colorFromHex(json['ribbon'] as String?) ?? kRibbonColors.first,
-      tint: colorFromHex(json['tint'] as String?) ?? kDiaryTints.first,
-      coverPath: serverFileRefOrNull(json['coverFileId'] as String?),
-      mutedNotices: {
-        for (final n in (json['mutedNotices'] as List?)?.whereType<String>() ?? const <String>[])
-          ?DiaryNotice.values.where((v) => v.name == n).firstOrNull,
-      },
+      ownerNickname: json['ownerNickname'] as String?,
+      memberCount: (json['memberCount'] as num?)?.toInt() ?? 1,
+      maxMembers: (json['maxMembers'] as num?)?.toInt() ?? kMaxDiaryMembers,
+      isMember: json['isMember'] as bool? ?? false,
     );
 
 /// 서버 저장소 — 사진은 저장할 때 올린다.
-/// 기록·댓글의 작성자가 로그인한 나이면 앱의 "나"(kMeAuthorId)로 바꿔 담는다 (하루 한 번 쓰기를 가린다).
+/// 작성자·멤버가 로그인한 나이면 앱의 "나"(kMeAuthorId)로 바꿔 담는다 (하루 한 번 쓰기·내 글 가리기).
 class ApiDiaryRepository implements DiaryRepository {
   ApiDiaryRepository({
     required Dio dio,
@@ -53,36 +111,43 @@ class ApiDiaryRepository implements DiaryRepository {
   final FileUploader _uploader;
   final String? Function() _myUserId;
 
-  /// 지금은 다이어리 주인만 쓰므로, 내 id 를 모르면(이전 버전에서 로그인) 모두 나로 본다
-  String _author(Object? id) {
+  @override
+  bool get canShare => true;
+
+  Diary _diary(Map<String, Object?> json) => diaryFromApi(json, myUserId: _myUserId());
+
+  DiaryPost _post(Map<String, Object?> json) {
     final me = _myUserId();
-    return me == null || id == me ? kMeAuthorId : id! as String;
+    return DiaryPost(
+      id: json['id']! as String,
+      diaryId: json['diaryId']! as String,
+      date: parseIsoDate(json['date']! as String),
+      createdAt: DateTime.parse(json['createdAt']! as String).toLocal(),
+      text: json['text'] as String? ?? '',
+      mood: Mood.byName(json['mood'] as String?),
+      photoPath: serverFileRefOrNull(json['photoFileId'] as String?),
+      authorId: _personId(json['authorId'], me),
+      author: _author(json, me),
+    );
   }
 
-  DiaryPost _post(Map<String, Object?> json) => DiaryPost(
-        id: json['id']! as String,
-        diaryId: json['diaryId']! as String,
-        date: parseIsoDate(json['date']! as String),
-        createdAt: DateTime.parse(json['createdAt']! as String).toLocal(),
-        text: json['text'] as String? ?? '',
-        mood: Mood.byName(json['mood'] as String?),
-        photoPath: serverFileRefOrNull(json['photoFileId'] as String?),
-        authorId: _author(json['authorId']),
-      );
-
-  DiaryComment _comment(Map<String, Object?> json) => DiaryComment(
-        id: json['id']! as String,
-        postId: json['postId']! as String,
-        text: json['text'] as String? ?? '',
-        createdAt: DateTime.parse(json['createdAt']! as String).toLocal(),
-        authorId: _author(json['authorId']),
-      );
+  DiaryComment _comment(Map<String, Object?> json) {
+    final me = _myUserId();
+    return DiaryComment(
+      id: json['id']! as String,
+      postId: json['postId']! as String,
+      text: json['text'] as String? ?? '',
+      createdAt: DateTime.parse(json['createdAt']! as String).toLocal(),
+      authorId: _personId(json['authorId'], me),
+      author: _author(json, me),
+    );
+  }
 
   @override
   Future<DiaryBook> fetch() async {
     if (!_session.hasSession) return DiaryBook.empty;
     return DiaryBook(
-      diaries: await fetchAllPages(_dio, _kDiariesPath, diaryFromApi),
+      diaries: await fetchAllPages(_dio, _kDiariesPath, _diary),
       posts: await fetchAllPages(_dio, _kPostsPath, _post),
       comments: await fetchAllPages(_dio, _kCommentsPath, _comment),
     );
@@ -95,6 +160,7 @@ class ApiDiaryRepository implements DiaryRepository {
     required Color ribbon,
     required Color tint,
     String? coverPath,
+    bool shared = false,
   }) async {
     final coverFileId = await _uploader.ensureUploaded(coverPath);
     try {
@@ -106,13 +172,14 @@ class ApiDiaryRepository implements DiaryRepository {
           'ribbon': hexOf(ribbon),
           'tint': hexOf(tint),
           'coverFileId': coverFileId,
+          'shared': shared,
         },
         // 가득 찬 경우는 화면이 "최대 6개" 로 직접 안내한다
         options: Options(extra: {
           kSilentCodesExtra: [kDiaryFullCode],
         }),
       );
-      return diaryFromApi(response.data!);
+      return _diary(response.data!);
     } on DioException catch (e) {
       final error = e.error;
       if (error is ApiException && error.code == kDiaryFullCode) return null;
@@ -129,12 +196,43 @@ class ApiDiaryRepository implements DiaryRepository {
         'targetIds': diary.targetIds,
         'ribbon': hexOf(diary.ribbon),
         'coverFileId': await _uploader.ensureUploaded(diary.coverPath),
-        'mutedNotices': [for (final n in diary.mutedNotices) n.name],
       },
     );
-    return diaryFromApi(response.data!);
+    return _diary(response.data!);
   }
 
+  @override
+  Future<void> setMutedNotices(String diaryId, Set<DiaryNotice> muted) => _dio.put<void>(
+        '$_kDiariesPath/$diaryId/muted-notices',
+        data: {'mutedNotices': [for (final n in muted) n.name]},
+      );
+
+  @override
+  Future<Diary> setShared(String diaryId, bool shared) async {
+    final response = await _dio.put<Map<String, dynamic>>('$_kDiariesPath/$diaryId/sharing', data: {'shared': shared});
+    return _diary(response.data!);
+  }
+
+  @override
+  Future<DiaryInvitation> previewInvitation(String code) async {
+    final response = await _dio.get<Map<String, dynamic>>('$_kInvitationsPath/${Uri.encodeComponent(code)}');
+    return diaryInvitationFromApi(code, response.data!);
+  }
+
+  @override
+  Future<DiaryBook> join(String code) async {
+    await _dio.post<Map<String, dynamic>>(_kMembershipsPath, data: {'code': code});
+    // 참여한 다이어리의 지난 기록·댓글까지 함께 보여야 하므로 모두 다시 읽는다
+    return fetch();
+  }
+
+  @override
+  Future<void> leave(String diaryId) => _dio.delete<void>('$_kDiariesPath/$diaryId/membership');
+
+  @override
+  Future<void> removeMember(String diaryId, String memberId) =>
+      _dio.delete<void>('$_kDiariesPath/$diaryId/members/$memberId');
+
   @override
   Future<void> deleteDiary(String diaryId) => _dio.delete<void>('$_kDiariesPath/$diaryId');
 
diff --git a/flutter/lib/features/diary/data/diary_repository.dart b/flutter/lib/features/diary/data/diary_repository.dart
index aee3ad9..01a97d3 100644
--- a/flutter/lib/features/diary/data/diary_repository.dart
+++ b/flutter/lib/features/diary/data/diary_repository.dart
@@ -12,6 +12,7 @@ import 'package:tma_app/features/auth/data/repositories/api_auth_repository.dart
 import 'package:tma_app/features/diary/data/api_diary_repository.dart';
 import 'package:tma_app/features/diary/domain/diary.dart';
 import 'package:tma_app/features/diary/domain/diary_book.dart';
+import 'package:tma_app/features/diary/domain/diary_invitation.dart';
 import 'package:tma_app/features/diary/domain/mood.dart';
 
 /// 다이어리 저장소 계약 — 서버(ApiDiaryRepository) / 기기(LocalDiaryRepository).
@@ -19,18 +20,40 @@ import 'package:tma_app/features/diary/domain/mood.dart';
 abstract interface class DiaryRepository {
   Future<DiaryBook> fetch();
 
-  /// 새 다이어리 — 책장이 가득 찼으면 null (서버 DIARY_001)
+  /// 공유 다이어리(초대·참여·멤버)를 쓸 수 있는지 — 다른 회원과 함께 쓰므로 서버가 있어야 한다
+  bool get canShare;
+
+  /// 새 다이어리 — 책장이 가득 찼으면 null (서버 DIARY_001). [shared] 면 처음부터 공유 다이어리
   Future<Diary?> createDiary({
     required String name,
     required List<String> targetIds,
     required Color ribbon,
     required Color tint,
     String? coverPath,
+    bool shared = false,
   });
 
-  /// 이름·대상·리본·표지·알림을 바꾼다 (바탕색은 만들 때 정한 값을 유지한다)
+  /// 이름·대상·리본·표지를 바꾼다 (주인만 · 바탕색은 만들 때 정한 값을 유지한다)
   Future<Diary> updateDiary(Diary diary);
 
+  /// 내 알림 설정 — 멤버마다 따로 둔다
+  Future<void> setMutedNotices(String diaryId, Set<DiaryNotice> muted);
+
+  /// 개인 ↔ 공유 전환 (주인만). 개인으로 바꾸면 다른 멤버는 모두 나간다
+  Future<Diary> setShared(String diaryId, bool shared);
+
+  /// 초대 코드로 참여할 다이어리를 미리 본다
+  Future<DiaryInvitation> previewInvitation(String code);
+
+  /// 초대 코드로 참여한다 — 참여한 다이어리의 기록·댓글까지 모두 다시 읽어 돌려준다
+  Future<DiaryBook> join(String code);
+
+  /// 참여한 다이어리에서 나간다 (주인이 아닐 때)
+  Future<void> leave(String diaryId);
+
+  /// 멤버를 내보낸다 (주인만)
+  Future<void> removeMember(String diaryId, String memberId);
+
   /// 다이어리와 그 안의 기록·댓글을 모두 지운다
   Future<void> deleteDiary(String diaryId);
 
@@ -59,6 +82,8 @@ abstract interface class DiaryRepository {
   Future<void> dropTarget(String targetId);
 }
 
+const String _kLocalNoSharing = '공유 다이어리는 서버 모드에서만 쓸 수 있다';
+
 const String _kDiariesKey = 'diary.diaries.v1';
 const String _kPostsKey = 'diary.posts.v1';
 const String _kCommentsKey = 'diary.comments.v1';
@@ -91,6 +116,9 @@ class LocalDiaryRepository implements DiaryRepository {
   @override
   Future<DiaryBook> fetch() async => _read();
 
+  @override
+  bool get canShare => false;
+
   /// 가득 찼는지는 알림기가 아이의 보관 여부까지 보고 먼저 확인한다
   @override
   Future<Diary?> createDiary({
@@ -99,6 +127,7 @@ class LocalDiaryRepository implements DiaryRepository {
     required Color ribbon,
     required Color tint,
     String? coverPath,
+    bool shared = false,
   }) async {
     final diary = Diary(
       id: _newId('d'),
@@ -118,6 +147,29 @@ class LocalDiaryRepository implements DiaryRepository {
     return diary;
   }
 
+  @override
+  Future<void> setMutedNotices(String diaryId, Set<DiaryNotice> muted) async {
+    final book = _read();
+    final diary = book.diary(diaryId);
+    if (diary != null) await _write(book.updateDiary(diary.copyWith(mutedNotices: muted)));
+  }
+
+  // 기기 저장 모드에는 함께 쓸 다른 회원이 없다 — 화면은 [canShare] 로 막는다
+  @override
+  Future<Diary> setShared(String diaryId, bool shared) => throw StateError(_kLocalNoSharing);
+
+  @override
+  Future<DiaryInvitation> previewInvitation(String code) => throw StateError(_kLocalNoSharing);
+
+  @override
+  Future<DiaryBook> join(String code) => throw StateError(_kLocalNoSharing);
+
+  @override
+  Future<void> leave(String diaryId) => throw StateError(_kLocalNoSharing);
+
+  @override
+  Future<void> removeMember(String diaryId, String memberId) => throw StateError(_kLocalNoSharing);
+
   @override
   Future<void> deleteDiary(String diaryId) async => _write(_read().deleteDiary(diaryId));
 
diff --git a/flutter/lib/features/diary/domain/diary.dart b/flutter/lib/features/diary/domain/diary.dart
index 0ff4723..ade8d85 100644
--- a/flutter/lib/features/diary/domain/diary.dart
+++ b/flutter/lib/features/diary/domain/diary.dart
@@ -12,9 +12,48 @@ const int kCommentMaxLength = 50;
 /// 다이어리 이름을 비워 두면 쓰는 이름
 const String kDefaultDiaryName = '새 다이어리';
 
-/// 기록한 사람 — 지금은 나 하나 (공유 다이어리가 생기면 회원 id)
+/// 기록한 사람이 나일 때의 id — 서버의 내 회원 id 도 이 값으로 바꿔 담는다 (하루 한 번 쓰기·내 글 가리기)
 const String kMeAuthorId = 'me';
 
+/// 공유 다이어리 한 권에 함께할 수 있는 사람 수 — 주인 포함 (시안 MAX_MEMBERS)
+const int kMaxDiaryMembers = 4;
+
+/// 닉네임을 모르는 사람
+const String kUnknownPersonName = '집사';
+
+/// 다이어리에 글·댓글을 남긴 사람 · 멤버
+class DiaryPerson {
+  const DiaryPerson({required this.id, this.nickname, this.photoPath});
+
+  /// 회원 id — 나이면 [kMeAuthorId]
+  final String id;
+  final String? nickname;
+  final String? photoPath;
+
+  bool get isMe => id == kMeAuthorId;
+
+  String get name => nickname ?? kUnknownPersonName;
+}
+
+/// 공유 다이어리의 멤버
+class DiaryMember extends DiaryPerson {
+  const DiaryMember({required super.id, super.nickname, super.photoPath, this.isOwner = false});
+
+  final bool isOwner;
+}
+
+/// 다른 사람의 다이어리에 담긴 아이 — 내 반려동물 목록에 없으므로 서버가 이름·사진을 함께 준다
+class DiaryTarget {
+  const DiaryTarget({required this.id, this.name, this.photoPath, this.isSelf = false});
+
+  final String id;
+  final String? name;
+  final String? photoPath;
+
+  /// 다이어리 주인 본인 (대상 "나")
+  final bool isSelf;
+}
+
 /// 책갈피 리본 색 선택지 (시안 RIBBON_SWATCHES)
 const List<Color> kRibbonColors = [
   Color(0xFFFFFFFF), Color(0xFF2B2622), Color(0xFFFF7500),
@@ -44,6 +83,11 @@ class Diary {
     required this.tint,
     this.coverPath,
     this.mutedNotices = const {},
+    this.shared = false,
+    this.isOwner = true,
+    this.inviteCode,
+    this.members = const [],
+    this.targets = const [],
   });
 
   final String id;
@@ -52,9 +96,10 @@ class Diary {
   /// 누구의 다이어리인지 — 반려동물 id 또는 나(self)
   final List<String> targetIds;
 
-  /// 대상이 모두 추억 보관함의 아이인지 — 그러면 책장에서 빠지고 보관함에서 본다
+  /// 대상이 모두 추억 보관함의 아이인지 — 그러면 책장에서 빠지고 보관함에서 본다.
+  /// 참여한 다이어리는 주인의 아이들이라 내 보관함과 상관없이 책장에 둔다
   bool isArchivedWith(Set<String> archivedPetIds) =>
-      targetIds.isNotEmpty && targetIds.every(archivedPetIds.contains);
+      isOwner && targetIds.isNotEmpty && targetIds.every(archivedPetIds.contains);
   final Color ribbon;
   final Color tint;
   final String? coverPath;
@@ -64,12 +109,41 @@ class Diary {
 
   bool notifies(DiaryNotice n) => !mutedNotices.contains(n);
 
+  /// 함께 쓰는 다이어리인지 (개인 다이어리는 false)
+  final bool shared;
+
+  /// 내가 만든 다이어리인지 — 아니면 초대받아 참여한 다이어리
+  final bool isOwner;
+
+  /// 멤버 초대 코드 — 주인에게만 온다
+  final String? inviteCode;
+
+  /// 함께 쓰는 사람들 (주인이 먼저). 개인 다이어리·기기 저장 모드는 비어 있다
+  final List<DiaryMember> members;
+
+  /// 참여한 다이어리의 아이들 (내 다이어리는 비어 있다 — 내 반려동물 목록으로 그린다)
+  final List<DiaryTarget> targets;
+
+  /// 멤버 수 — 나만 쓰면 1
+  int get memberCount => members.isEmpty ? 1 : members.length;
+
+  bool get membersFull => memberCount >= kMaxDiaryMembers;
+
+  /// 다이어리를 만든 사람
+  DiaryMember? get owner => members.where((m) => m.isOwner).firstOrNull;
+
+  /// 첫 아이 이름 — 내 다이어리는 [myTargetNames](내 반려동물·나)에서, 참여한 다이어리는 서버가 준 이름으로
+  String? firstTargetName(Map<String, String> myTargetNames) => isOwner
+      ? targetIds.map((id) => myTargetNames[id]).nonNulls.firstOrNull
+      : targets.map((t) => t.name).nonNulls.firstOrNull;
+
   Diary copyWith({
     String? name,
     List<String>? targetIds,
     Color? ribbon,
     String? coverPath,
     Set<DiaryNotice>? mutedNotices,
+    List<DiaryMember>? members,
   }) =>
       Diary(
         id: id,
@@ -79,6 +153,11 @@ class Diary {
         tint: tint,
         coverPath: coverPath ?? this.coverPath,
         mutedNotices: mutedNotices ?? this.mutedNotices,
+        shared: shared,
+        isOwner: isOwner,
+        inviteCode: inviteCode,
+        members: members ?? this.members,
+        targets: targets,
       );
 
   Map<String, Object?> toJson() => {
@@ -116,6 +195,7 @@ class DiaryPost {
     this.mood,
     this.photoPath,
     this.authorId = kMeAuthorId,
+    this.author,
   });
 
   final String id;
@@ -131,6 +211,11 @@ class DiaryPost {
   final String? photoPath;
   final String authorId;
 
+  /// 남이 쓴 기록이면 그 사람 (내 기록은 null — 내 프로필로 그린다)
+  final DiaryPerson? author;
+
+  bool get isMine => authorId == kMeAuthorId;
+
   bool get hasPhoto => photoPath != null;
 
   DiaryPost copyWith({String? text}) => DiaryPost(
@@ -142,6 +227,7 @@ class DiaryPost {
         mood: mood,
         photoPath: photoPath,
         authorId: authorId,
+        author: author,
       );
 
   Map<String, Object?> toJson() => {
@@ -175,6 +261,7 @@ class DiaryComment {
     required this.text,
     required this.createdAt,
     this.authorId = kMeAuthorId,
+    this.author,
   });
 
   final String id;
@@ -183,8 +270,19 @@ class DiaryComment {
   final DateTime createdAt;
   final String authorId;
 
-  DiaryComment copyWith({String? text}) =>
-      DiaryComment(id: id, postId: postId, text: text ?? this.text, createdAt: createdAt, authorId: authorId);
+  /// 남이 쓴 댓글이면 그 사람 (내 댓글은 null)
+  final DiaryPerson? author;
+
+  bool get isMine => authorId == kMeAuthorId;
+
+  DiaryComment copyWith({String? text}) => DiaryComment(
+        id: id,
+        postId: postId,
+        text: text ?? this.text,
+        createdAt: createdAt,
+        authorId: authorId,
+        author: author,
+      );
 
   Map<String, Object?> toJson() => {
         'id': id,
diff --git a/flutter/lib/features/diary/domain/diary_invitation.dart b/flutter/lib/features/diary/domain/diary_invitation.dart
new file mode 100644
index 0000000..fc97daa
--- /dev/null
+++ b/flutter/lib/features/diary/domain/diary_invitation.dart
@@ -0,0 +1,43 @@
+/// 공유 다이어리 초대 — 참여하기 전에 확인하는 다이어리 정보
+class DiaryInvitation {
+  const DiaryInvitation({
+    required this.code,
+    required this.diaryId,
+    required this.name,
+    required this.ownerNickname,
+    required this.memberCount,
+    required this.maxMembers,
+    required this.isMember,
+  });
+
+  final String code;
+  final String diaryId;
+  final String name;
+  final String? ownerNickname;
+  final int memberCount;
+  final int maxMembers;
+
+  /// 이미 함께 쓰고 있는 다이어리인지 (내가 만든 다이어리 포함)
+  final bool isMember;
+
+  bool get isFull => memberCount >= maxMembers;
+}
+
+/// 초대 코드 앞머리 (서버가 `RUP-` + 6자로 만든다)
+const String kInviteCodePrefix = 'RUP-';
+
+/// 초대 QR 에 담는 주소 — 앱의 스캐너가 읽는다
+String diaryInviteLink(String code) => 'rup://diary-invite/$code';
+
+final RegExp _kInviteBody = RegExp(r'^[A-Z0-9]{6}$');
+
+/// QR 또는 직접 입력한 값에서 초대 코드를 꺼낸다 — 주소(rup://diary-invite/RUP-8F3K2Q)·
+/// 코드(RUP-8F3K2Q, 소문자도)·앞머리 없이 쓴 6자(8F3K2Q) 모두 받는다. 초대 코드가 아니면 null
+String? parseInviteCode(String raw) {
+  var text = raw.trim();
+  const link = 'rup://diary-invite/';
+  if (text.startsWith(link)) text = text.substring(link.length);
+  text = text.split('?').first.trim().toUpperCase().replaceAll(' ', '');
+  if (text.startsWith(kInviteCodePrefix)) text = text.substring(kInviteCodePrefix.length);
+  return _kInviteBody.hasMatch(text) ? '$kInviteCodePrefix$text' : null;
+}
diff --git a/flutter/lib/features/diary/presentation/pages/diary_page.dart b/flutter/lib/features/diary/presentation/pages/diary_page.dart
index a103552..14a2002 100644
--- a/flutter/lib/features/diary/presentation/pages/diary_page.dart
+++ b/flutter/lib/features/diary/presentation/pages/diary_page.dart
@@ -3,6 +3,7 @@ import 'dart:async';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:go_router/go_router.dart';
+import 'package:tma_app/core/api/api_guard.dart';
 import 'package:tma_app/core/constants/app_colors.dart';
 import 'package:tma_app/core/constants/app_sizes.dart';
 import 'package:tma_app/core/router/app_routes.dart';
@@ -55,6 +56,9 @@ const double _kTabBottomGap = 30;
 /// 다이어리 머리가 위아래로 2씩 좁다 (시안 embedded margin 2px 0 16px — 기록 탭·보관함 모두)
 const double _kEmbeddedTrim = 2;
 
+/// 멤버 수 칩 바탕 (시안 #F6F4EF)
+const Color _kChipBg = Color(0xFFF6F4EF);
+
 /// 다이어리 안 — 기록 피드(모두·사진·글) / 달력 보기, 검색, 오늘 쓰기
 class DiaryPage extends ConsumerStatefulWidget {
   const DiaryPage({super.key, required this.diaryId, this.archived = false});
@@ -79,6 +83,10 @@ class _DiaryPageState extends ConsumerState<DiaryPage> {
   void initState() {
     super.initState();
     _query.addListener(() => setState(() {}));
+    // 함께 쓰는 다이어리면 들어올 때 다른 멤버의 새 기록을 다시 읽는다
+    if (ref.read(diaryBookProvider).diary(widget.diaryId)?.shared ?? false) {
+      unawaited(succeeded(ref.read(diaryProvider.notifier).refresh()));
+    }
   }
 
   @override
@@ -139,10 +147,16 @@ class _DiaryPageState extends ConsumerState<DiaryPage> {
                   onBack: () => context.pop(),
                   trailing: archived
                       ? null
-                      : _HeaderIconButton(
-                          label: '다이어리 설정',
-                          onTap: () => unawaited(context.push(AppRoutes.diarySettings(diary.id))),
-                          child: const RupGlyphIcon(RupGlyph.gear, size: 21, color: AppColors.ink2),
+                      : Row(
+                          mainAxisSize: MainAxisSize.min,
+                          children: [
+                            if (diary.shared) ...[_MembersChip(count: diary.memberCount), const SizedBox(width: AppSpacing.sm)],
+                            _HeaderIconButton(
+                              label: '다이어리 설정',
+                              onTap: () => unawaited(context.push(AppRoutes.diarySettings(diary.id))),
+                              child: const RupGlyphIcon(RupGlyph.gear, size: 21, color: AppColors.ink2),
+                            ),
+                          ],
                         ),
                 ),
                 Row(
@@ -311,6 +325,42 @@ class _NoPosts extends StatelessWidget {
   }
 }
 
+/// 공유 다이어리 멤버 수 (시안 .rup-memseg__chip.is-solo)
+class _MembersChip extends StatelessWidget {
+  const _MembersChip({required this.count});
+
+  final int count;
+
+  @override
+  Widget build(BuildContext context) {
+    return Semantics(
+      label: '멤버 $count명 (최대 $kMaxDiaryMembers명)',
+      excludeSemantics: true,
+      child: Container(
+        height: 34,
+        padding: const EdgeInsets.symmetric(horizontal: 13),
+        decoration: BoxDecoration(color: _kChipBg, borderRadius: BorderRadius.circular(AppRadius.pill)),
+        child: Row(
+          mainAxisSize: MainAxisSize.min,
+          children: [
+            const RupIcon(RupIconName.users, size: 14, stroke: 2, color: AppColors.ink2),
+            const SizedBox(width: 5),
+            Text(
+              '$count/$kMaxDiaryMembers',
+              style: Theme.of(context).textTheme.bodySmall!.copyWith(
+                    fontSize: 12.5,
+                    fontWeight: FontWeight.w700,
+                    color: AppColors.ink2,
+                    height: AppTypography.normalHeight,
+                  ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
 class _HeaderIconButton extends StatelessWidget {
   const _HeaderIconButton({required this.label, required this.onTap, required this.child});
 
diff --git a/flutter/lib/features/diary/presentation/pages/diary_settings_page.dart b/flutter/lib/features/diary/presentation/pages/diary_settings_page.dart
index e896e7a..8bc2dfa 100644
--- a/flutter/lib/features/diary/presentation/pages/diary_settings_page.dart
+++ b/flutter/lib/features/diary/presentation/pages/diary_settings_page.dart
@@ -10,11 +10,14 @@ import 'package:tma_app/core/router/app_routes.dart';
 import 'package:tma_app/core/theme/app_typography.dart';
 import 'package:tma_app/features/diary/domain/diary.dart';
 import 'package:tma_app/features/diary/presentation/providers/diary_providers.dart';
+import 'package:tma_app/features/diary/presentation/widgets/diary_join.dart';
+import 'package:tma_app/features/diary/presentation/widgets/diary_sharing_sections.dart';
 import 'package:tma_app/features/diary/presentation/widgets/diary_sheets.dart';
 import 'package:tma_app/features/records/presentation/providers/records_tab_provider.dart';
 import 'package:tma_app/shared/widgets/heart_toggle.dart';
 import 'package:tma_app/shared/widgets/icons/rup_icon.dart';
 import 'package:tma_app/shared/widgets/pressable.dart';
+import 'package:tma_app/shared/widgets/rup_button.dart';
 import 'package:tma_app/shared/widgets/rup_card.dart';
 import 'package:tma_app/shared/widgets/rup_dialog.dart';
 import 'package:tma_app/shared/widgets/rup_toast.dart';
@@ -24,6 +27,9 @@ import 'package:tma_app/shared/widgets/sub_page_header.dart';
 
 const double _kNormal = AppTypography.normalHeight;
 
+/// 나가기·전환 확인창의 경고 색 (시안 #E05A4A)
+const Color _kWarn = Color(0xFFE05A4A);
+
 /// 알림 줄 — 아이콘·색·제목·설명 (시안 NOTIF_ROWS)
 typedef _NoticeRow = ({DiaryNotice notice, RupIconName icon, Color tint, String title, String desc});
 
@@ -33,155 +39,261 @@ const List<_NoticeRow> _kNoticeRows = [
   (notice: DiaryNotice.reminder, icon: RupIconName.paw, tint: AppColors.accent, title: '우리 아이 기록 알림', desc: '오늘 일기를 쓰지 않았을 때 잊지 않도록 알려드려요.'),
 ];
 
-/// 다이어리 설정 — 정보 수정 · 개인/공유 · 알림 · 제거
-class DiarySettingsPage extends ConsumerWidget {
+/// 다이어리 설정 — 정보 수정 · 개인/공유 · 멤버 · 알림 · 초대 · 나가기/제거
+class DiarySettingsPage extends ConsumerStatefulWidget {
   const DiarySettingsPage({super.key, required this.diaryId});
 
   final String diaryId;
 
-  Future<void> _delete(BuildContext context, WidgetRef ref, Diary diary) async {
+  @override
+  ConsumerState<DiarySettingsPage> createState() => _DiarySettingsPageState();
+}
+
+class _DiarySettingsPageState extends ConsumerState<DiarySettingsPage> {
+  /// "N명 더 초대할 수 있어요" 를 누르면 내려갈 곳
+  final _inviteKey = GlobalKey();
+
+  DiaryNotifier get _diaries => ref.read(diaryProvider.notifier);
+  ToastNotifier get _toast => ref.read(toastProvider.notifier);
+
+  /// 책장으로 돌아간다 — 지우거나 나간 다이어리를 그리지 않게 먼저 화면을 바꾼다
+  void _backToShelf() {
+    ref.read(recordsTabProvider.notifier).select(RecordsTab.diary);
+    context.go(AppRoutes.records);
+  }
+
+  Future<void> _delete(Diary diary) async {
     final ok = await showRupRemoveConfirm(
       context,
       title: '다이어리를 제거할까요?',
       message: '다이어리를 삭제하면 다시 복구할 수 없으며,\n이때까지 적은 기록이 전부 삭제돼요.',
     );
-    if (!ok || !context.mounted) return;
-    // 먼저 책장으로 돌아가 지워진 다이어리를 그리지 않게 한다
-    ref.read(recordsTabProvider.notifier).select(RecordsTab.diary);
-    context.go(AppRoutes.records);
-    if (!await succeeded(ref.read(diaryProvider.notifier).deleteDiary(diary.id))) return;
-    ref.read(toastProvider.notifier).show('다이어리를 제거했어요');
+    if (!ok || !mounted) return;
+    final diaries = _diaries;
+    final toast = _toast;
+    _backToShelf();
+    if (!await succeeded(diaries.deleteDiary(diary.id))) return;
+    toast.show('다이어리를 제거했어요');
+  }
+
+  /// 개인 ↔ 공유 — 개인으로 바꾸면 함께 쓰던 멤버가 모두 나가므로 먼저 묻는다
+  Future<void> _setShared(Diary diary, bool shared) async {
+    if (shared == diary.shared) return;
+    if (!_diaries.canShare) {
+      _toast.show(kSharedDiaryLocalOnly, icon: RupIconName.users);
+      return;
+    }
+    if (!shared && diary.memberCount > 1) {
+      final ok = await showRupConfirm(
+        context,
+        title: '개인 다이어리로 전환할까요?',
+        message: '함께 기록하던 멤버 ${diary.memberCount - 1}명이 모두 다이어리에서 나가게 돼요.\n이 작업은 되돌릴 수 없어요.',
+        confirmLabel: '전환하기',
+        layout: RupConfirmLayout.row,
+        icon: RupIconName.alert,
+        iconColor: _kWarn,
+      );
+      if (!ok || !mounted) return;
+    }
+    if (!await succeeded(_diaries.setShared(diary.id, shared: shared))) return;
+    _toast.show(shared ? '공유 다이어리로 전환했어요' : '개인 다이어리로 전환했어요',
+        icon: shared ? RupIconName.users : RupIconName.check);
+  }
+
+  Future<void> _remove(Diary diary, DiaryMember member) async {
+    final name = memberName(ref, member);
+    final ok = await showRupConfirm(
+      context,
+      title: '$name님을 내보낼까요?',
+      message: '내보낸 멤버는 더 이상 이 다이어리를 보거나 기록할 수 없어요.',
+      confirmLabel: '내보내기',
+      layout: RupConfirmLayout.row,
+      leading: MemberAvatar(person: member, size: 52),
+    );
+    if (!ok || !mounted) return;
+    if (!await succeeded(_diaries.removeMember(diary.id, member.id))) return;
+    _toast.show('$name님을 내보냈어요');
+  }
+
+  Future<void> _leave(Diary diary) async {
+    final ok = await showRupConfirm(
+      context,
+      title: '다이어리에서 나갈까요?',
+      message: '공유 다이어리는 한번 나가면\n주인이 다시 초대해주지 않으면 다시 들어올 수 없어요.',
+      confirmLabel: '나가기',
+      layout: RupConfirmLayout.row,
+      icon: RupIconName.alert,
+      iconColor: _kWarn,
+    );
+    if (!ok || !mounted) return;
+    final diaries = _diaries;
+    final toast = _toast;
+    _backToShelf();
+    if (!await succeeded(diaries.leave(diary.id))) return;
+    toast.show('다이어리에서 나왔어요');
+  }
+
+  void _jumpToInvite() {
+    final target = _inviteKey.currentContext;
+    if (target != null) {
+      unawaited(Scrollable.ensureVisible(target, duration: const Duration(milliseconds: 350), curve: Curves.easeOut));
+    }
   }
 
   @override
-  Widget build(BuildContext context, WidgetRef ref) {
-    final diary = ref.watch(diaryBookProvider).diary(diaryId);
+  Widget build(BuildContext context) {
+    final diary = ref.watch(diaryBookProvider).diary(widget.diaryId);
     if (diary == null) return const Scaffold(body: SizedBox.shrink());
     final textTheme = Theme.of(context).textTheme;
+    final code = diary.inviteCode;
+    final canInvite = diary.isOwner && diary.shared && !diary.membersFull && code != null;
 
     return Scaffold(
       body: SafeArea(
         bottom: false,
-        child: ListView(
+        child: SingleChildScrollView(
           padding: EdgeInsets.fromLTRB(
             AppSpacing.xl,
             AppSpacing.xs,
             AppSpacing.xl,
             MediaQuery.paddingOf(context).bottom + 40,
           ),
-          children: [
-            SubPageHeader(
-              title: '다이어리 설정',
-              subtitle: diary.name,
-              displayFont: true,
-              onBack: () => context.pop(),
-              trailing: Pressable(
-                onTap: () => unawaited(showDiaryFormSheet(context, editing: diary)),
-                pressedScale: .9,
-                semanticLabel: '다이어리 수정하기',
-                child: const SizedBox(
-                  width: 30,
-                  height: 34,
-                  child: Center(child: RupIcon(RupIconName.pencilCute, size: 25, stroke: 1.9, color: AppColors.ink2)),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.stretch,
+            children: [
+              SubPageHeader(
+                title: '다이어리 설정',
+                subtitle: diary.name,
+                displayFont: true,
+                onBack: () => context.pop(),
+                // 다이어리 정보는 주인만 고친다
+                trailing: diary.isOwner
+                    ? Pressable(
+                        onTap: () => unawaited(showDiaryFormSheet(context, editing: diary)),
+                        pressedScale: .9,
+                        semanticLabel: '다이어리 수정하기',
+                        child: const SizedBox(
+                          width: 30,
+                          height: 34,
+                          child: Center(child: RupIcon(RupIconName.pencilCute, size: 25, stroke: 1.9, color: AppColors.ink2)),
+                        ),
+                      )
+                    : null,
+              ),
+              const SizedBox(height: 2),
+              if (diary.isOwner)
+                SegToggle<bool>(
+                  large: true,
+                  first: (false, '개인 다이어리'),
+                  second: (true, '공유 다이어리'),
+                  value: diary.shared,
+                  iconOf: (shared, on) => RupIcon(shared ? RupIconName.users : RupIconName.user, size: 18, stroke: on ? 2.4 : 1.9),
+                  onChanged: (shared) => unawaited(_setShared(diary, shared)),
+                )
+              else
+                JoinedDiaryCard(diary: diary),
+              if (diary.shared) ...[
+                SizedBox(height: diary.isOwner ? 24 : 22),
+                SharingSectionTitle(title: '멤버', count: '${diary.memberCount}/$kMaxDiaryMembers'),
+                const SizedBox(height: AppSpacing.md),
+                DiaryMembersCard(
+                  diary: diary,
+                  onRemove: (m) => unawaited(_remove(diary, m)),
+                  onInvite: _jumpToInvite,
+                ),
+              ],
+              const SizedBox(height: 26),
+              const Padding(
+                padding: EdgeInsets.symmetric(horizontal: AppSpacing.xs),
+                child: SectionTitle(title: '알림 설정'),
+              ),
+              const SizedBox(height: AppSpacing.md),
+              RupCard(
+                child: Column(
+                  children: [
+                    for (final (i, row) in _kNoticeRows.indexed)
+                      Container(
+                        padding: const EdgeInsets.symmetric(horizontal: AppSpacing.lg, vertical: 14),
+                        decoration: BoxDecoration(
+                          border: i == 0 ? null : const Border(top: BorderSide(color: AppColors.line2)),
+                        ),
+                        child: Row(
+                          children: [
+                            Container(
+                              width: 36,
+                              height: 36,
+                              decoration: BoxDecoration(
+                                color: row.tint.withValues(alpha: .14),
+                                borderRadius: BorderRadius.circular(11),
+                              ),
+                              alignment: Alignment.center,
+                              child: RupIcon(row.icon, size: 19, stroke: 2, color: row.tint),
+                            ),
+                            const SizedBox(width: 13),
+                            Expanded(
+                              child: Column(
+                                crossAxisAlignment: CrossAxisAlignment.start,
+                                children: [
+                                  Text(
+                                    row.title,
+                                    style: textTheme.titleSmall!.copyWith(fontSize: 14.5, height: _kNormal),
+                                  ),
+                                  const SizedBox(height: 2),
+                                  Text(
+                                    row.desc,
+                                    style: textTheme.bodySmall!.copyWith(color: AppColors.muted, height: 1.45),
+                                  ),
+                                ],
+                              ),
+                            ),
+                            const SizedBox(width: 13),
+                            HeartToggle(
+                              value: diary.notifies(row.notice),
+                              label: row.title,
+                              onChanged: (on) => unawaited(succeeded(_diaries.setNotice(diary, row.notice, on: on))),
+                            ),
+                          ],
+                        ),
+                      ),
+                  ],
                 ),
               ),
-            ),
-            const SizedBox(height: 2),
-            SegToggle<bool>(
-              large: true,
-              first: (false, '개인 다이어리'),
-              second: (true, '공유 다이어리'),
-              value: false,
-              iconOf: (shared, on) => RupIcon(shared ? RupIconName.users : RupIconName.user, size: 18, stroke: on ? 2.4 : 1.9),
-              onChanged: (shared) {
-                if (shared) ref.read(toastProvider.notifier).show(kSharedDiarySoon, icon: RupIconName.users);
-              },
-            ),
-            const SizedBox(height: 26),
-            const Padding(
-              padding: EdgeInsets.symmetric(horizontal: AppSpacing.xs),
-              child: SectionTitle(title: '알림 설정'),
-            ),
-            const SizedBox(height: AppSpacing.md),
-            RupCard(
-              child: Column(
-                children: [
-                  for (final (i, row) in _kNoticeRows.indexed)
-                    Container(
-                      padding: const EdgeInsets.symmetric(horizontal: AppSpacing.lg, vertical: 14),
-                      decoration: BoxDecoration(
-                        border: i == 0 ? null : const Border(top: BorderSide(color: AppColors.line2)),
+              const SizedBox(height: 22),
+              if (canInvite) DiaryInviteSection(key: _inviteKey, diary: diary, code: code),
+              if (!diary.isOwner)
+                RupButton(
+                  label: '다이어리 나가기',
+                  variant: RupButtonVariant.ghost,
+                  foreground: _kWarn,
+                  leading: const RupIcon(RupIconName.logout, size: 17, stroke: 2, color: _kWarn),
+                  onPressed: () => unawaited(_leave(diary)),
+                )
+              else ...[
+                const SizedBox(height: 22),
+                Semantics(
+                  container: true,
+                  button: true,
+                  child: GestureDetector(
+                    behavior: HitTestBehavior.opaque,
+                    onTap: () => unawaited(_delete(diary)),
+                    child: Padding(
+                      padding: const EdgeInsets.symmetric(vertical: AppSpacing.sm),
+                      child: Text(
+                        '다이어리 제거',
+                        textAlign: TextAlign.center,
+                        style: textTheme.bodyMedium!.copyWith(
+                          fontSize: 13.5,
+                          fontWeight: FontWeight.w700,
+                          color: AppColors.muted,
+                          height: _kNormal,
+                        ),
                       ),
-                      child: Row(
-                        children: [
-                          Container(
-                            width: 36,
-                            height: 36,
-                            decoration: BoxDecoration(
-                              color: row.tint.withValues(alpha: .14),
-                              borderRadius: BorderRadius.circular(11),
-                            ),
-                            alignment: Alignment.center,
-                            child: RupIcon(row.icon, size: 19, stroke: 2, color: row.tint),
-                          ),
-                          const SizedBox(width: 13),
-                          Expanded(
-                            child: Column(
-                              crossAxisAlignment: CrossAxisAlignment.start,
-                              children: [
-                                Text(
-                                  row.title,
-                                  style: textTheme.titleSmall!.copyWith(fontSize: 14.5, height: _kNormal),
-                                ),
-                                const SizedBox(height: 2),
-                                Text(
-                                  row.desc,
-                                  style: textTheme.bodySmall!.copyWith(color: AppColors.muted, height: 1.45),
-                                ),
-                              ],
-                            ),
-                          ),
-                          const SizedBox(width: 13),
-                          HeartToggle(
-                            value: diary.notifies(row.notice),
-                            label: row.title,
-                            onChanged: (on) => unawaited(succeeded(ref.read(diaryProvider.notifier).updateDiary(
-                                  diary.copyWith(
-                                    mutedNotices: on
-                                        ? ({...diary.mutedNotices}..remove(row.notice))
-                                        : {...diary.mutedNotices, row.notice},
-                                  ),
-                                ))),
-                          ),
-                        ],
-                      ),
-                    ),
-                ],
-              ),
-            ),
-            const SizedBox(height: 44),
-            Semantics(
-              container: true,
-              button: true,
-              child: GestureDetector(
-                behavior: HitTestBehavior.opaque,
-                onTap: () => unawaited(_delete(context, ref, diary)),
-                child: Padding(
-                  padding: const EdgeInsets.symmetric(vertical: AppSpacing.sm),
-                  child: Text(
-                    '다이어리 제거',
-                    textAlign: TextAlign.center,
-                    style: textTheme.bodyMedium!.copyWith(
-                      fontSize: 13.5,
-                      fontWeight: FontWeight.w700,
-                      color: AppColors.muted,
-                      height: _kNormal,
                     ),
                   ),
                 ),
-              ),
-            ),
-          ],
+              ],
+            ],
+          ),
         ),
       ),
     );
diff --git a/flutter/lib/features/diary/presentation/providers/diary_providers.dart b/flutter/lib/features/diary/presentation/providers/diary_providers.dart
index fa03ea5..9758ead 100644
--- a/flutter/lib/features/diary/presentation/providers/diary_providers.dart
+++ b/flutter/lib/features/diary/presentation/providers/diary_providers.dart
@@ -7,6 +7,7 @@ import 'package:tma_app/core/utils/date_format.dart';
 import 'package:tma_app/features/diary/data/diary_repository.dart';
 import 'package:tma_app/features/diary/domain/diary.dart';
 import 'package:tma_app/features/diary/domain/diary_book.dart';
+import 'package:tma_app/features/diary/domain/diary_invitation.dart';
 import 'package:tma_app/features/diary/domain/mood.dart';
 import 'package:tma_app/features/pet/presentation/providers/pet_providers.dart';
 
@@ -28,20 +29,28 @@ class DiaryNotifier extends AsyncNotifier<DiaryBook> {
     if (ref.mounted) state = AsyncData(next);
   }
 
+  /// 공유 다이어리를 쓸 수 있는지 (서버 모드)
+  bool get canShare => _repo.canShare;
+
+  /// 책장이 가득 찼는지 — 보관함으로 간 다이어리는 세지 않는다
+  bool get atMax => _book.atMax(ref.read(petListProvider).value?.archivedIds ?? const {});
+
   /// 새 다이어리 — 가득 찼으면 null
   Future<Diary?> createDiary({
     required String name,
     required List<String> targetIds,
     required Color ribbon,
     String? coverPath,
+    bool shared = false,
   }) async {
-    if (_book.atMax(ref.read(petListProvider).value?.archivedIds ?? const {})) return null;
+    if (atMax) return null;
     final diary = await _repo.createDiary(
       name: name.trim().isEmpty ? kDefaultDiaryName : name.trim(),
       targetIds: targetIds,
       ribbon: ribbon,
       tint: kDiaryTints[Random().nextInt(kDiaryTints.length)],
       coverPath: coverPath,
+      shared: shared,
     );
     if (diary != null) _set(_book.addDiary(diary));
     return diary;
@@ -54,6 +63,43 @@ class DiaryNotifier extends AsyncNotifier<DiaryBook> {
     _set(_book.deleteDiary(id));
   }
 
+  /// 내 알림 하나를 켜거나 끈다
+  Future<void> setNotice(Diary diary, DiaryNotice notice, {required bool on}) async {
+    final muted = on ? ({...diary.mutedNotices}..remove(notice)) : {...diary.mutedNotices, notice};
+    await _repo.setMutedNotices(diary.id, muted);
+    final latest = _book.diary(diary.id);
+    if (latest != null) _set(_book.updateDiary(latest.copyWith(mutedNotices: muted)));
+  }
+
+  // ── 공유 다이어리 ────────────────────────────────────────
+  /// 다른 멤버가 새로 남긴 기록·댓글을 다시 읽는다 — 불러오는 중 화면 없이 바꿔 끼운다
+  Future<void> refresh() async {
+    // 기기 저장 모드는 나만 쓰므로 다시 읽을 것이 없다
+    if (!_repo.canShare) return;
+    _set(await _repo.fetch());
+  }
+
+  /// 개인 ↔ 공유 전환 (주인만)
+  Future<void> setShared(String id, {required bool shared}) async =>
+      _set(_book.updateDiary(await _repo.setShared(id, shared)));
+
+  Future<DiaryInvitation> previewInvitation(String code) => _repo.previewInvitation(code);
+
+  /// 초대 코드로 참여 — 참여한 다이어리의 기록까지 다시 읽는다
+  Future<void> join(String code) async => _set(await _repo.join(code));
+
+  /// 참여한 다이어리에서 나간다 — 내 책장에서 그 다이어리와 기록이 사라진다
+  Future<void> leave(String id) async {
+    await _repo.leave(id);
+    _set(_book.deleteDiary(id));
+  }
+
+  /// 멤버를 내보낸다 (주인만) — 서버가 초대 코드를 새로 바꾸므로 다시 읽는다
+  Future<void> removeMember(String diaryId, String memberId) async {
+    await _repo.removeMember(diaryId, memberId);
+    _set(await _repo.fetch());
+  }
+
   Future<void> addPost({required String diaryId, required String text, Mood? mood, String? photoPath}) async {
     final post = await _repo.addPost(
       diaryId: diaryId,
diff --git a/flutter/lib/features/diary/presentation/widgets/diary_cover.dart b/flutter/lib/features/diary/presentation/widgets/diary_cover.dart
index 4af5e3f..161942a 100644
--- a/flutter/lib/features/diary/presentation/widgets/diary_cover.dart
+++ b/flutter/lib/features/diary/presentation/widgets/diary_cover.dart
@@ -2,6 +2,7 @@ import 'dart:ui' show ImageFilter;
 
 import 'package:flutter/material.dart';
 import 'package:flutter_svg/flutter_svg.dart';
+import 'package:tma_app/core/constants/app_assets.dart';
 import 'package:tma_app/core/constants/app_colors.dart';
 import 'package:tma_app/core/constants/app_sizes.dart';
 import 'package:tma_app/core/theme/app_shadows.dart';
@@ -12,6 +13,8 @@ import 'package:tma_app/features/pet/presentation/widgets/pet_photo_image.dart';
 import 'package:tma_app/features/pet/presentation/widgets/target_avatar.dart';
 import 'package:tma_app/shared/widgets/dashed_border_box.dart';
 import 'package:tma_app/shared/widgets/icons/rup_icon.dart';
+import 'package:tma_app/shared/widgets/person_avatar.dart';
+import 'package:tma_app/shared/widgets/photo_image.dart';
 
 /// 표지 가로:세로 1:1.16 (시안 aspectRatio 1 / 1.16)
 const double kDiaryCoverAspect = 1 / 1.16;
@@ -91,8 +94,8 @@ class DiaryCoverTile extends StatelessWidget {
                       ),
                     ),
                   ),
-                  Positioned(top: -2, right: 15, child: DiaryRibbon(color: diary.ribbon)),
-                  if (showTargets) Positioned(left: 12, top: 11, child: _CoverTargets(ids: diary.targetIds)),
+                  Positioned(top: -2, right: 15, child: DiaryRibbon(color: diary.ribbon, shared: diary.shared)),
+                  if (showTargets) Positioned(left: 12, top: 11, child: _CoverTargets(diary: diary)),
                   Positioned(
                     left: 14,
                     right: 12,
@@ -137,23 +140,27 @@ class DiaryCoverTile extends StatelessWidget {
 
 /// 표지 왼쪽 위 아이들 — 조금씩 겹쳐 놓는다
 class _CoverTargets extends StatelessWidget {
-  const _CoverTargets({required this.ids});
+  const _CoverTargets({required this.diary});
 
-  final List<String> ids;
+  final Diary diary;
 
   static const double _size = 28;
   static const double _overlap = 8;
 
   @override
   Widget build(BuildContext context) {
-    if (ids.isEmpty) return const SizedBox.shrink();
+    // 참여한 다이어리의 아이들은 내 반려동물 목록에 없다 — 서버가 준 이름·사진으로 그린다
+    final avatars = diary.isOwner
+        ? [for (final id in diary.targetIds) TargetAvatar(targetId: id, size: _size)]
+        : [for (final t in diary.targets) _SharedTargetAvatar(target: t, size: _size)];
+    if (avatars.isEmpty) return const SizedBox.shrink();
     return SizedBox(
       height: _size,
-      width: _size + (ids.length - 1) * (_size - _overlap),
+      width: _size + (avatars.length - 1) * (_size - _overlap),
       child: Stack(
         clipBehavior: Clip.none,
         children: [
-          for (final (i, id) in ids.indexed)
+          for (final (i, avatar) in avatars.indexed)
             Positioned(
               left: i * (_size - _overlap),
               child: DecoratedBox(
@@ -162,7 +169,7 @@ class _CoverTargets extends StatelessWidget {
                   color: Colors.white,
                   boxShadow: [BoxShadow(color: Colors.white.withValues(alpha: .9), spreadRadius: 2)],
                 ),
-                child: TargetAvatar(targetId: id, size: _size),
+                child: avatar,
               ),
             ),
         ],
@@ -171,6 +178,35 @@ class _CoverTargets extends StatelessWidget {
   }
 }
 
+/// 참여한 다이어리의 아이 — 주인 본인("나")이면 사람 사진, 아이면 아이 사진 (없으면 기본 얼굴)
+class _SharedTargetAvatar extends StatelessWidget {
+  const _SharedTargetAvatar({required this.target, required this.size});
+
+  final DiaryTarget target;
+  final double size;
+
+  @override
+  Widget build(BuildContext context) {
+    if (target.isSelf) return PersonAvatar(size: size, photoPath: target.photoPath, background: AppColors.primary50);
+    final photo = target.photoPath;
+    final placeholder = SvgPicture.asset(AppAssets.petDefault, fit: BoxFit.cover);
+    return Semantics(
+      label: target.name == null ? null : '${target.name} 사진',
+      image: true,
+      child: Container(
+        width: size,
+        height: size,
+        decoration: const BoxDecoration(shape: BoxShape.circle, color: _kSharedTargetFill),
+        clipBehavior: Clip.antiAlias,
+        child: photo == null ? placeholder : PhotoImage(path: photo, fallback: placeholder),
+      ),
+    );
+  }
+}
+
+/// 사진 없는 아이 바탕 — PetAvatar 와 같은 옅은 회색
+const Color _kSharedTargetFill = Color(0x0A000000);
+
 /// 책갈피 리본 — 반투명 유리 느낌(뒤를 흐리게) + 고른 색
 class DiaryRibbon extends StatelessWidget {
   const DiaryRibbon({super.key, required this.color, this.shared = false});
diff --git a/flutter/lib/features/diary/presentation/widgets/diary_join.dart b/flutter/lib/features/diary/presentation/widgets/diary_join.dart
new file mode 100644
index 0000000..69bacd5
--- /dev/null
+++ b/flutter/lib/features/diary/presentation/widgets/diary_join.dart
@@ -0,0 +1,299 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
+import 'package:tma_app/core/api/api_guard.dart';
+import 'package:tma_app/core/api/error_lexicon.dart';
+import 'package:tma_app/core/constants/app_colors.dart';
+import 'package:tma_app/core/constants/app_sizes.dart';
+import 'package:tma_app/core/router/app_routes.dart';
+import 'package:tma_app/core/theme/app_shadows.dart';
+import 'package:tma_app/core/theme/app_typography.dart';
+import 'package:tma_app/features/diary/domain/diary.dart';
+import 'package:tma_app/features/diary/domain/diary_invitation.dart';
+import 'package:tma_app/features/diary/presentation/providers/diary_providers.dart';
+import 'package:tma_app/shared/widgets/icons/rup_icon.dart';
+import 'package:tma_app/shared/widgets/pressable.dart';
+import 'package:tma_app/shared/widgets/qr_scanner_page.dart';
+import 'package:tma_app/shared/widgets/rup_button.dart';
+import 'package:tma_app/shared/widgets/rup_dialog.dart';
+import 'package:tma_app/shared/widgets/rup_form_fields.dart';
+import 'package:tma_app/shared/widgets/rup_sheet.dart';
+import 'package:tma_app/shared/widgets/rup_toast.dart';
+
+/// 공유 다이어리(초대·참여·멤버)는 다른 회원과 함께 쓰므로 서버가 있어야 한다
+const String kSharedDiaryLocalOnly = '기기 저장 모드에서는 공유 다이어리를 쓸 수 없어요';
+
+/// 초대 코드 입력칸 최대 길이 (시안 maxLength 12)
+const int _kCodeMaxLength = 12;
+
+/// 공유 다이어리 참여 스캐너 문구
+const QrScanCopy _kScanCopy = QrScanCopy(
+  title: '공유 다이어리 참여',
+  hint: '초대받은 다이어리의 QR 코드를\n사각형 안에 비춰주세요.',
+  foundHint: '초대 QR을 찾았어요!',
+  manualLabel: '초대 코드 입력하기',
+  unavailableHint: '카메라를 쓸 수 없어요.\n설정에서 카메라 권한을 허용하거나 초대 코드를 입력해 주세요.',
+);
+
+/// 공유 다이어리 참여 스캐너 — 초대 QR 을 비추면 참여할 다이어리를 불러온다
+class DiaryJoinScannerPage extends StatelessWidget {
+  const DiaryJoinScannerPage({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return QrScannerPage<DiaryInvitation>(
+      copy: _kScanCopy,
+      parse: parseInviteCode,
+      // 초대 QR 이 아니면 서버가 못 찾았을 때와 같은 안내
+      invalidMessage: ErrorLexicon.getMessage('DIARY_003'),
+      load: (ref, code) => ref.read(diaryProvider.notifier).previewInvitation(code),
+    );
+  }
+}
+
+/// 참여하기 시트에서 고른 것 — QR 스캔으로 가거나, 코드로 찾은 초대
+sealed class _JoinChoice {
+  const _JoinChoice();
+}
+
+final class _ChoseScan extends _JoinChoice {
+  const _ChoseScan();
+}
+
+final class _Found extends _JoinChoice {
+  const _Found(this.invitation);
+
+  final DiaryInvitation invitation;
+}
+
+/// 공유 다이어리 참여 — 참여하기 시트(QR 스캔 / 코드 입력) → 확인 → 참여
+Future<void> startJoiningDiary(BuildContext context, WidgetRef ref) async {
+  final diaries = ref.read(diaryProvider.notifier);
+  final toast = ref.read(toastProvider.notifier);
+  if (!diaries.canShare) {
+    toast.show(kSharedDiaryLocalOnly, icon: RupIconName.users);
+    return;
+  }
+  if (diaries.atMax) {
+    toast.show('다이어리는 최대 $kMaxDiaries개까지예요', icon: RupIconName.alert);
+    return;
+  }
+
+  DiaryInvitation? invitation;
+  // 스캐너에서 "초대 코드 입력하기"를 누르면 시트로 돌아온다
+  while (invitation == null) {
+    if (!context.mounted) return;
+    final choice = await showRupSheet<_JoinChoice>(
+      context,
+      title: '공유 다이어리 참여',
+      builder: (_) => const _JoinBody(),
+    );
+    if (!context.mounted) return;
+    switch (choice) {
+      case null:
+        return;
+      case _Found(invitation: final found):
+        return _confirmJoin(context, ref, found);
+      case _ChoseScan():
+        final outcome = await context.push<ScanOutcome<DiaryInvitation>>(AppRoutes.diaryJoinScan);
+        switch (outcome) {
+          case ScanFound(:final value):
+            invitation = value;
+          case ScanTypeCode():
+            continue;
+          case null:
+            return;
+        }
+    }
+  }
+  if (context.mounted) await _confirmJoin(context, ref, invitation);
+}
+
+/// 참여 전 확인 — 이미 함께 쓰거나 자리가 없으면 서버와 같은 안내로 멈춘다
+Future<void> _confirmJoin(BuildContext context, WidgetRef ref, DiaryInvitation invitation) async {
+  final toast = ref.read(toastProvider.notifier);
+  if (invitation.isMember) {
+    toast.show(ErrorLexicon.getMessage('DIARY_005'), icon: RupIconName.alert);
+    return;
+  }
+  if (invitation.isFull) {
+    toast.show(ErrorLexicon.getMessage('DIARY_004'), icon: RupIconName.alert);
+    return;
+  }
+  final ok = await showRupConfirm(
+    context,
+    title: '${invitation.name}에\n참여하시겠어요?',
+    titleSpan: TextSpan(children: [
+      TextSpan(text: invitation.name, style: const TextStyle(color: AppColors.primary600)),
+      const TextSpan(text: '에\n참여하시겠어요?'),
+    ]),
+    message: '공유 다이어리에 참여해서\n아이에 대한 기록을 함께 작성해봐요!',
+    confirmLabel: '참여하기',
+    layout: RupConfirmLayout.row,
+    glyph: RupGlyph.diaryShared,
+    iconColor: AppColors.accent,
+    iconBackground: AppColors.accent100,
+  );
+  if (!ok) return;
+  if (!await succeeded(ref.read(diaryProvider.notifier).join(invitation.code))) return;
+  toast.show('공유 다이어리에 참여했어요');
+}
+
+/// 참여하기 시트 — QR 스캔 / 또는 / 초대 코드 입력 + 참여하기
+class _JoinBody extends ConsumerStatefulWidget {
+  const _JoinBody();
+
+  @override
+  ConsumerState<_JoinBody> createState() => _JoinBodyState();
+}
+
+class _JoinBodyState extends ConsumerState<_JoinBody> {
+  final _code = TextEditingController();
+  bool _busy = false;
+
+  @override
+  void initState() {
+    super.initState();
+    // 입력이 생기면 버튼을 켠다
+    _code.addListener(() => setState(() {}));
+  }
+
+  @override
+  void dispose() {
+    _code.dispose();
+    super.dispose();
+  }
+
+  Future<void> _submit() async {
+    if (_busy) return;
+    final toast = ref.read(toastProvider.notifier);
+    if (_code.text.trim().isEmpty) {
+      toast.show('초대 코드를 입력해주세요', icon: RupIconName.alert);
+      return;
+    }
+    final code = parseInviteCode(_code.text);
+    if (code == null) {
+      // 초대 코드 모양이 아니다 — 서버가 못 찾았을 때와 같은 안내
+      toast.show(ErrorLexicon.getMessage('DIARY_003'), icon: RupIconName.alert);
+      return;
+    }
+    setState(() => _busy = true);
+    try {
+      final invitation = await ref.read(diaryProvider.notifier).previewInvitation(code);
+      if (mounted) Navigator.of(context).pop(_Found(invitation));
+    } catch (e) {
+      if (!isReportedApiFailure(e)) rethrow;
+      if (mounted) setState(() => _busy = false);
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final textTheme = Theme.of(context).textTheme;
+    TextStyle ui(double size, FontWeight weight, Color color) =>
+        textTheme.bodyMedium!.copyWith(fontSize: size, fontWeight: weight, color: color, height: AppTypography.normalHeight);
+
+    return SingleChildScrollView(
+      child: Padding(
+        padding: const EdgeInsets.only(top: AppSpacing.xs),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.stretch,
+          children: [
+            // 1) QR 스캔 — 가장 빠른 방법
+            Pressable(
+              pressedScale: 1,
+              pressedBrightness: .97,
+              onTap: () => Navigator.of(context).pop(const _ChoseScan()),
+              child: Container(
+                padding: const EdgeInsets.symmetric(horizontal: 15, vertical: AppSpacing.lg),
+                decoration: BoxDecoration(
+                  color: AppColors.primary50,
+                  borderRadius: BorderRadius.circular(15),
+                  border: Border.all(color: AppColors.primary100, width: 1.5),
+                ),
+                child: Row(
+                  children: [
+                    Container(
+                      width: 40,
+                      height: 40,
+                      decoration: BoxDecoration(
+                        color: AppColors.surface,
+                        borderRadius: BorderRadius.circular(AppSpacing.md),
+                        boxShadow: AppShadows.sm,
+                      ),
+                      alignment: Alignment.center,
+                      child: const RupIcon(RupIconName.qrcode, color: AppColors.primary),
+                    ),
+                    const SizedBox(width: 13),
+                    Expanded(
+                      child: Column(
+                        crossAxisAlignment: CrossAxisAlignment.start,
+                        children: [
+                          Text('QR 코드 스캔', style: ui(15, FontWeight.w700, AppColors.ink)),
+                          const SizedBox(height: 2),
+                          Text('초대 QR을 비추면 바로 확인돼요', style: ui(12, FontWeight.w400, AppColors.muted)),
+                        ],
+                      ),
+                    ),
+                    const RupIcon(RupIconName.chevR, size: 17, color: AppColors.muted),
+                  ],
+                ),
+              ),
+            ),
+            // 구분선 + "또는" (시안 .rup-orline)
+            Padding(
+              padding: const EdgeInsets.symmetric(vertical: 18),
+              child: Row(
+                children: [
+                  const Expanded(child: Divider(height: 1, thickness: 1, color: AppColors.line2)),
+                  Padding(
+                    padding: const EdgeInsets.symmetric(horizontal: 10),
+                    child: Text('또는', style: ui(12, FontWeight.w700, AppColors.muted)),
+                  ),
+                  const Expanded(child: Divider(height: 1, thickness: 1, color: AppColors.line2)),
+                ],
+              ),
+            ),
+            // 2) 초대 코드 직접 입력
+            RupField(
+              label: '초대 코드 입력',
+              child: RupTextField(
+                controller: _code,
+                hintText: 'RUP-8F3K2Q',
+                maxLength: _kCodeMaxLength,
+                textInputAction: TextInputAction.done,
+                textAlign: TextAlign.center,
+                textStyle: const TextStyle(
+                  fontFamily: AppFonts.display,
+                  fontSize: 19,
+                  letterSpacing: 19 * .06,
+                  height: AppTypography.displayNormalHeight,
+                ),
+                inputFormatters: [_UpperCaseFormatter()],
+                onSubmitted: (_) => unawaited(_submit()),
+              ),
+            ),
+            const SizedBox(height: AppSpacing.md),
+            RupButton(
+              label: '참여하기',
+              large: true,
+              dimmed: _code.text.trim().isEmpty || _busy,
+              dimmedOpacity: .45,
+              onPressed: () => unawaited(_submit()),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+/// 초대 코드는 대문자로 받는다 (시안 toUpperCase)
+class _UpperCaseFormatter extends TextInputFormatter {
+  @override
+  TextEditingValue formatEditUpdate(TextEditingValue oldValue, TextEditingValue newValue) =>
+      newValue.copyWith(text: newValue.text.toUpperCase());
+}
diff --git a/flutter/lib/features/diary/presentation/widgets/diary_post_card.dart b/flutter/lib/features/diary/presentation/widgets/diary_post_card.dart
index ec74d4d..f492d5b 100644
--- a/flutter/lib/features/diary/presentation/widgets/diary_post_card.dart
+++ b/flutter/lib/features/diary/presentation/widgets/diary_post_card.dart
@@ -37,17 +37,21 @@ TextStyle _ui(BuildContext context, double size, FontWeight weight, Color color,
 TextStyle _display(double size, {FontWeight weight = FontWeight.w700, Color color = AppColors.ink}) =>
     TextStyle(fontFamily: AppFonts.display, fontSize: size, fontWeight: weight, color: color, height: AppTypography.displayNormalHeight);
 
-/// 글쓴이 아바타 — 지금은 나 하나
+/// 글쓴이 아바타 — 남이면 그 사람 사진, 나면(null) 내 프로필 사진
 class _AuthorAvatar extends ConsumerWidget {
-  const _AuthorAvatar({required this.size});
+  const _AuthorAvatar({required this.size, this.author});
 
   final double size;
+  final DiaryPerson? author;
 
   @override
   Widget build(BuildContext context, WidgetRef ref) =>
-      PersonAvatar(size: size, photoPath: ref.watch(profileProvider).photoPath);
+      PersonAvatar(size: size, photoPath: author == null ? ref.watch(profileProvider).photoPath : author!.photoPath);
 }
 
+/// 글쓴이 이름 — 남이면 그 사람 닉네임, 나면 내 닉네임
+String _authorName(WidgetRef ref, DiaryPerson? author) => author?.name ?? ref.watch(userNicknameProvider);
+
 /// 글쓴이 · 날짜 · 기분 · ⋮
 class _PostMeta extends ConsumerWidget {
   const _PostMeta({required this.post, required this.onMenu, this.avatar = 28, this.nameSize = 13});
@@ -62,20 +66,21 @@ class _PostMeta extends ConsumerWidget {
     final mood = post.mood;
     return Row(
       children: [
-        _AuthorAvatar(size: avatar),
+        _AuthorAvatar(size: avatar, author: post.author),
         SizedBox(width: avatar > 30 ? 10 : 9),
         Expanded(
           child: Column(
             crossAxisAlignment: CrossAxisAlignment.start,
             children: [
-              Text(ref.watch(userNicknameProvider), style: _display(nameSize)),
+              Text(_authorName(ref, post.author), style: _display(nameSize)),
               const SizedBox(height: 1),
               Text(relativeDayLabel(post.date, DateTime.now()), style: _ui(context, 11, FontWeight.w400, AppColors.muted)),
             ],
           ),
         ),
-        if (mood != null) ...[MoodIcon(mood: mood, size: 22), const SizedBox(width: 9)],
-        _MoreButton(onTap: onMenu),
+        if (mood != null) ...[MoodIcon(mood: mood, size: 22), if (post.isMine) const SizedBox(width: 9)],
+        // 수정·삭제는 쓴 사람만
+        if (post.isMine) _MoreButton(onTap: onMenu),
       ],
     );
   }
@@ -323,7 +328,6 @@ class _CommentsState extends ConsumerState<_Comments> {
   @override
   Widget build(BuildContext context) {
     final comments = ref.watch(diaryBookProvider.select((b) => b.commentsOf(widget.postId)));
-    final name = ref.watch(userNicknameProvider);
     final muted = _ui(context, 12, FontWeight.w600, AppColors.muted);
 
     return Container(
@@ -343,7 +347,7 @@ class _CommentsState extends ConsumerState<_Comments> {
               child: Row(
                 crossAxisAlignment: CrossAxisAlignment.start,
                 children: [
-                  const _AuthorAvatar(size: 30),
+                  _AuthorAvatar(size: 30, author: c.author),
                   const SizedBox(width: 9),
                   Expanded(
                     child: Column(
@@ -351,8 +355,8 @@ class _CommentsState extends ConsumerState<_Comments> {
                       children: [
                         Row(
                           children: [
-                            Expanded(child: Text(name, style: _display(12.5))),
-                            if (_editingId != c.id) ...[
+                            Expanded(child: Text(_authorName(ref, c.author), style: _display(12.5))),
+                            if (c.isMine && _editingId != c.id) ...[
                               _SmallAction(label: '수정', style: muted, onTap: () => setState(() {
                                     _editingId = c.id;
                                     _edit.text = c.text;
@@ -558,29 +562,30 @@ class PhotoPostTile extends StatelessWidget {
           fit: StackFit.expand,
           children: [
             ColoredBox(color: AppColors.primary50, child: PetPhotoImage(path: post.photoPath!)),
-            Positioned(
-              top: 7,
-              right: 7,
-              child: Semantics(
-                button: true,
-                label: '기록 관리',
-                excludeSemantics: true,
-                child: GestureDetector(
-                  onTap: onMenu,
-                  child: Container(
-                    width: 28,
-                    height: 28,
-                    decoration: BoxDecoration(
-                      color: Colors.white.withValues(alpha: .9),
-                      shape: BoxShape.circle,
-                      boxShadow: const [BoxShadow(color: Color(0x2E000000), blurRadius: 4, offset: Offset(0, 1))],
+            if (post.isMine)
+              Positioned(
+                top: 7,
+                right: 7,
+                child: Semantics(
+                  button: true,
+                  label: '기록 관리',
+                  excludeSemantics: true,
+                  child: GestureDetector(
+                    onTap: onMenu,
+                    child: Container(
+                      width: 28,
+                      height: 28,
+                      decoration: BoxDecoration(
+                        color: Colors.white.withValues(alpha: .9),
+                        shape: BoxShape.circle,
+                        boxShadow: const [BoxShadow(color: Color(0x2E000000), blurRadius: 4, offset: Offset(0, 1))],
+                      ),
+                      alignment: Alignment.center,
+                      child: const RupIcon(RupIconName.moreV, size: 17, color: AppColors.ink2),
                     ),
-                    alignment: Alignment.center,
-                    child: const RupIcon(RupIconName.moreV, size: 17, color: AppColors.ink2),
                   ),
                 ),
               ),
-            ),
           ],
         ),
       ),
diff --git a/flutter/lib/features/diary/presentation/widgets/diary_sharing_sections.dart b/flutter/lib/features/diary/presentation/widgets/diary_sharing_sections.dart
new file mode 100644
index 0000000..d59e104
--- /dev/null
+++ b/flutter/lib/features/diary/presentation/widgets/diary_sharing_sections.dart
@@ -0,0 +1,467 @@
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:qr_flutter/qr_flutter.dart';
+import 'package:tma_app/core/constants/app_colors.dart';
+import 'package:tma_app/core/constants/app_sizes.dart';
+import 'package:tma_app/core/theme/app_shadows.dart';
+import 'package:tma_app/core/theme/app_typography.dart';
+import 'package:tma_app/features/auth/presentation/providers/user_provider.dart';
+import 'package:tma_app/features/diary/domain/diary.dart';
+import 'package:tma_app/features/diary/domain/diary_invitation.dart';
+import 'package:tma_app/features/mypage/data/profile_repository.dart';
+import 'package:tma_app/shared/widgets/blurred_modal.dart';
+import 'package:tma_app/shared/widgets/dashed_border_box.dart';
+import 'package:tma_app/shared/widgets/icons/rup_icon.dart';
+import 'package:tma_app/shared/widgets/person_avatar.dart';
+import 'package:tma_app/shared/widgets/pressable.dart';
+import 'package:tma_app/shared/widgets/rup_button.dart';
+import 'package:tma_app/shared/widgets/rup_card.dart';
+import 'package:tma_app/shared/widgets/rup_toast.dart';
+
+const double _kNormal = AppTypography.normalHeight;
+const double _kMemberAvatar = 40;
+const double _kInviteQr = 150;
+const double _kZoomQr = 230;
+
+TextStyle _ui(BuildContext context, double size, FontWeight weight, Color color) =>
+    Theme.of(context).textTheme.bodyMedium!.copyWith(fontSize: size, fontWeight: weight, color: color, height: _kNormal);
+
+/// 섹션 제목 (시안 .rup-section-title h2) — 옆에 작은 보조 글
+class SharingSectionTitle extends StatelessWidget {
+  const SharingSectionTitle({super.key, required this.title, this.count});
+
+  final String title;
+  final String? count;
+
+  @override
+  Widget build(BuildContext context) {
+    final textTheme = Theme.of(context).textTheme;
+    return Padding(
+      padding: const EdgeInsets.symmetric(horizontal: AppSpacing.xs),
+      child: Row(
+        crossAxisAlignment: CrossAxisAlignment.baseline,
+        textBaseline: TextBaseline.alphabetic,
+        children: [
+          Text(
+            title,
+            style: textTheme.titleMedium!.copyWith(fontWeight: FontWeight.w600, height: AppTypography.displayNormalHeight),
+          ),
+          if (count != null) ...[
+            const SizedBox(width: 9),
+            Text(count!, style: _ui(context, 13, FontWeight.w700, AppColors.muted)),
+          ],
+        ],
+      ),
+    );
+  }
+}
+
+/// 멤버 사진 — 나면 내 프로필 사진
+class MemberAvatar extends ConsumerWidget {
+  const MemberAvatar({super.key, required this.person, required this.size});
+
+  final DiaryPerson person;
+  final double size;
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final photo = person.isMe ? ref.watch(profileProvider).photoPath : person.photoPath;
+    return PersonAvatar(size: size, photoPath: photo);
+  }
+}
+
+/// 멤버 이름 — 나면 내 닉네임
+String memberName(WidgetRef ref, DiaryPerson person) => person.isMe ? ref.watch(userNicknameProvider) : person.name;
+
+/// 멤버 목록 — 주인 표시, 주인이 보면 "내보내기", 자리가 남으면 초대 줄
+class DiaryMembersCard extends ConsumerWidget {
+  const DiaryMembersCard({super.key, required this.diary, required this.onRemove, required this.onInvite});
+
+  final Diary diary;
+  final ValueChanged<DiaryMember> onRemove;
+
+  /// 초대 줄을 누르면 아래 "멤버 초대하기" 로 내려간다
+  final VoidCallback onInvite;
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final rows = <Widget>[
+      for (final m in diary.members)
+        _MemberRow(
+          avatar: MemberAvatar(person: m, size: _kMemberAvatar),
+          name: '${memberName(ref, m)}${m.isMe ? ' (나)' : ''}',
+          trailing: m.isOwner
+              ? const _OwnerBadge()
+              : diary.isOwner
+                  ? _KickButton(name: memberName(ref, m), onTap: () => onRemove(m))
+                  : null,
+        ),
+      if (diary.isOwner && !diary.membersFull)
+        Pressable(
+          pressedScale: 1,
+          pressedOpacity: .7,
+          onTap: onInvite,
+          child: _MemberRow(
+            avatar: const DashedBorderBox(
+              color: AppColors.line,
+              strokeWidth: 2,
+              radius: _kMemberAvatar / 2,
+              child: SizedBox.square(
+                dimension: _kMemberAvatar - 4,
+                child: Center(child: RupIcon(RupIconName.plus, size: 20, stroke: 2.2, color: AppColors.muted)),
+              ),
+            ),
+            name: '${kMaxDiaryMembers - diary.memberCount}명 더 초대할 수 있어요',
+            muted: true,
+            trailing: const RupIcon(RupIconName.chevR, size: 17, color: AppColors.muted),
+          ),
+        ),
+    ];
+    return RupCard(
+      child: Column(
+        children: [
+          for (final (i, row) in rows.indexed)
+            DecoratedBox(
+              decoration: BoxDecoration(border: i == 0 ? null : const Border(top: BorderSide(color: AppColors.line2))),
+              child: row,
+            ),
+        ],
+      ),
+    );
+  }
+}
+
+class _MemberRow extends StatelessWidget {
+  const _MemberRow({required this.avatar, required this.name, this.trailing, this.muted = false});
+
+  final Widget avatar;
+  final String name;
+  final Widget? trailing;
+
+  /// 초대 줄 — 흐린 작은 글
+  final bool muted;
+
+  @override
+  Widget build(BuildContext context) {
+    return Padding(
+      padding: const EdgeInsets.symmetric(horizontal: 15, vertical: 13),
+      child: Row(
+        children: [
+          avatar,
+          const SizedBox(width: AppSpacing.md),
+          Expanded(
+            child: Text(
+              name,
+              maxLines: 1,
+              overflow: TextOverflow.ellipsis,
+              style: muted
+                  ? _ui(context, 13.5, FontWeight.w600, AppColors.muted)
+                  : _ui(context, 15, FontWeight.w700, AppColors.ink),
+            ),
+          ),
+          if (trailing != null) ...[const SizedBox(width: AppSpacing.sm), trailing!],
+        ],
+      ),
+    );
+  }
+}
+
+/// "내보내기" — 작은 흰 버튼 (시안 .rup-btn--ghost, 7/13 · 12.5)
+class _KickButton extends StatelessWidget {
+  const _KickButton({required this.name, required this.onTap});
+
+  final String name;
+  final VoidCallback onTap;
+
+  @override
+  Widget build(BuildContext context) {
+    return Pressable(
+      onTap: onTap,
+      semanticLabel: '$name님 내보내기',
+      child: Container(
+        padding: const EdgeInsets.symmetric(horizontal: 13, vertical: 7),
+        decoration: BoxDecoration(
+          color: AppColors.surface,
+          borderRadius: BorderRadius.circular(AppRadius.pill),
+          border: Border.all(color: AppColors.line, width: 1.5),
+        ),
+        child: Text('내보내기', style: AppTypography.button(12.5, color: AppColors.ink)),
+      ),
+    );
+  }
+}
+
+/// "주인" 표시 (시안: primary-50 바탕, primary-100 테두리)
+class _OwnerBadge extends StatelessWidget {
+  const _OwnerBadge();
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      padding: const EdgeInsets.symmetric(horizontal: 9, vertical: 3),
+      decoration: BoxDecoration(
+        color: AppColors.primary50,
+        borderRadius: BorderRadius.circular(AppSpacing.sm),
+        border: Border.all(color: AppColors.primary100),
+      ),
+      child: Text('주인', style: _ui(context, 11.5, FontWeight.w700, AppColors.primary600)),
+    );
+  }
+}
+
+/// 참여한 다이어리 — 누가 만든 다이어리인지 (주인이 아닐 때 개인/공유 선택 대신)
+class JoinedDiaryCard extends ConsumerWidget {
+  const JoinedDiaryCard({super.key, required this.diary});
+
+  final Diary diary;
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    final owner = diary.owner;
+    return RupCard(
+      padding: const EdgeInsets.all(AppSpacing.lg),
+      child: Row(
+        children: [
+          Container(
+            width: 40,
+            height: 40,
+            decoration: BoxDecoration(color: AppColors.accent100, borderRadius: BorderRadius.circular(AppSpacing.md)),
+            alignment: Alignment.center,
+            child: const RupIcon(RupIconName.users, size: 21, stroke: 2, color: AppColors.accent),
+          ),
+          const SizedBox(width: 11),
+          Expanded(
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text('공유 다이어리', style: _ui(context, 14.5, FontWeight.w700, AppColors.ink)),
+                const SizedBox(height: 1),
+                Text(
+                  '${owner == null ? kUnknownPersonName : memberName(ref, owner)}님이 만든 다이어리예요',
+                  style: _ui(context, 12, FontWeight.w400, AppColors.muted),
+                ),
+              ],
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+/// 초대 코드 복사 — 클립보드에 넣고 알린다
+Future<void> copyInviteCode(WidgetRef ref, String code) async {
+  final toast = ref.read(toastProvider.notifier);
+  await Clipboard.setData(ClipboardData(text: code));
+  toast.show('초대 코드를 복사했어요', icon: RupIconName.copy);
+}
+
+/// 초대 QR — 가운데 다이어리 표시
+class _InviteQr extends StatelessWidget {
+  const _InviteQr({required this.code, required this.size, required this.badge, required this.padding});
+
+  final String code;
+  final double size;
+  final double badge;
+  final double padding;
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      padding: EdgeInsets.all(padding),
+      decoration: BoxDecoration(
+        color: Colors.white,
+        borderRadius: BorderRadius.circular(padding + 6),
+        border: Border.all(color: AppColors.line),
+        boxShadow: AppShadows.sm,
+      ),
+      child: Stack(
+        alignment: Alignment.center,
+        children: [
+          QrImageView(
+            data: diaryInviteLink(code),
+            size: size,
+            padding: EdgeInsets.zero,
+            errorCorrectionLevel: QrErrorCorrectLevel.H,
+            semanticsLabel: '다이어리 초대 QR 코드',
+          ),
+          Container(
+            width: badge,
+            height: badge,
+            decoration: BoxDecoration(
+              color: AppColors.primary,
+              borderRadius: BorderRadius.circular(badge * .32),
+              boxShadow: [BoxShadow(color: Colors.white, spreadRadius: badge / 10)],
+            ),
+            alignment: Alignment.center,
+            child: RupGlyphIcon(RupGlyph.diary, size: badge / 2, color: Colors.white),
+          ),
+        ],
+      ),
+    );
+  }
+}
+
+/// 멤버 초대하기 — QR(누르면 커진다) + 초대 코드 복사 + 안내
+class DiaryInviteSection extends ConsumerWidget {
+  const DiaryInviteSection({super.key, required this.diary, required this.code});
+
+  final Diary diary;
+  final String code;
+
+  Future<void> _zoom(BuildContext context, WidgetRef ref) {
+    return showBlurredDialog<void>(
+      context,
+      builder: (dialogContext) => Dialog(
+        backgroundColor: Colors.transparent,
+        elevation: 0,
+        insetPadding: const EdgeInsets.all(AppSpacing.xl),
+        child: ConstrainedBox(
+          constraints: const BoxConstraints(maxWidth: 330),
+          child: RupCard(
+            padding: const EdgeInsets.all(AppSpacing.lg),
+            child: Column(
+              mainAxisSize: MainAxisSize.min,
+              children: [
+                Text('초대 QR', style: _ui(dialogContext, 17, FontWeight.w800, AppColors.ink)),
+                const SizedBox(height: AppSpacing.xs),
+                Text.rich(
+                  TextSpan(children: [
+                    const TextSpan(text: '상대방이 rup 카메라로 스캔하면\n'),
+                    TextSpan(text: diary.name, style: const TextStyle(fontWeight: FontWeight.w700, color: AppColors.ink)),
+                    const TextSpan(text: '에 함께 기록해요.'),
+                  ]),
+                  textAlign: TextAlign.center,
+                  style: _ui(dialogContext, 13, FontWeight.w400, AppColors.ink2).copyWith(height: 1.55),
+                ),
+                const SizedBox(height: 18),
+                _InviteQr(code: code, size: _kZoomQr, badge: 56, padding: 18),
+                const SizedBox(height: 18),
+                Text(
+                  code,
+                  style: const TextStyle(
+                    fontFamily: AppFonts.display,
+                    fontSize: 24,
+                    letterSpacing: 24 * .08,
+                    height: AppTypography.displayNormalHeight,
+                    color: AppColors.ink,
+                  ),
+                ),
+                const SizedBox(height: 16),
+                RupButton(
+                  label: '초대 코드 복사',
+                  large: true,
+                  variant: RupButtonVariant.soft,
+                  leading: const RupIcon(RupIconName.copy, size: 17, stroke: 2.1, color: AppColors.primary600),
+                  onPressed: () => unawaited(copyInviteCode(ref, code)),
+                ),
+              ],
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.stretch,
+      children: [
+        const SharingSectionTitle(title: '멤버 초대하기'),
+        Padding(
+          padding: const EdgeInsets.fromLTRB(AppSpacing.xs, AppSpacing.xs, AppSpacing.xs, AppSpacing.lg),
+          child: Text(
+            'QR코드 혹은 초대코드로 함께 기록할 사람을 불러보세요.',
+            style: _ui(context, 13, FontWeight.w400, AppColors.muted).copyWith(height: 1.55),
+          ),
+        ),
+        Center(
+          child: Semantics(
+            button: true,
+            label: '초대 QR 크게 보기',
+            child: GestureDetector(
+              onTap: () => unawaited(_zoom(context, ref)),
+              child: _InviteQr(code: code, size: _kInviteQr, badge: 40, padding: 14),
+            ),
+          ),
+        ),
+        const SizedBox(height: 9),
+        Row(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: [
+            const RupIcon(RupIconName.search, size: 13, stroke: 2, color: AppColors.muted),
+            const SizedBox(width: AppSpacing.xs),
+            Text('탭하면 QR이 커져요', style: _ui(context, 11.5, FontWeight.w400, AppColors.muted)),
+          ],
+        ),
+        const SizedBox(height: 14),
+        Semantics(
+          button: true,
+          label: '초대 코드 복사',
+          child: GestureDetector(
+            onTap: () => unawaited(copyInviteCode(ref, code)),
+            child: Container(
+              padding: const EdgeInsets.symmetric(horizontal: 15, vertical: 13),
+              decoration: BoxDecoration(
+                color: AppColors.surface,
+                borderRadius: BorderRadius.circular(14),
+                border: Border.all(color: AppColors.line, width: 1.5),
+              ),
+              child: Row(
+                children: [
+                  Expanded(
+                    child: Column(
+                      crossAxisAlignment: CrossAxisAlignment.start,
+                      children: [
+                        Text('초대 코드', style: _ui(context, 12, FontWeight.w700, AppColors.muted)),
+                        const SizedBox(height: 2),
+                        Text(
+                          code,
+                          style: const TextStyle(
+                            fontFamily: AppFonts.display,
+                            fontSize: 21,
+                            letterSpacing: 21 * .06,
+                            height: AppTypography.displayNormalHeight,
+                            color: AppColors.ink,
+                          ),
+                        ),
+                      ],
+                    ),
+                  ),
+                  const RupIcon(RupIconName.copy, size: 19, stroke: 2, color: AppColors.primary),
+                ],
+              ),
+            ),
+          ),
+        ),
+        Padding(
+          padding: const EdgeInsets.fromLTRB(AppSpacing.xs, AppSpacing.lg, AppSpacing.xs, 22),
+          child: Row(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              const Padding(
+                padding: EdgeInsets.only(top: 1),
+                child: RupIcon(RupIconName.alert, size: 15, stroke: 2.2, color: AppColors.primary),
+              ),
+              const SizedBox(width: AppSpacing.sm),
+              Expanded(
+                child: Text.rich(
+                  const TextSpan(children: [
+                    TextSpan(text: '받은 사람은 '),
+                    TextSpan(text: '다이어리 추가 → 공유 다이어리 참여하기', style: TextStyle(fontWeight: FontWeight.w700)),
+                    TextSpan(text: '에서 코드를 입력하면 함께 기록할 수 있어요.'),
+                  ]),
+                  style: _ui(context, 12.5, FontWeight.w400, AppColors.ink2).copyWith(height: 1.55),
+                ),
+              ),
+            ],
+          ),
+        ),
+      ],
+    );
+  }
+}
diff --git a/flutter/lib/features/diary/presentation/widgets/diary_sheets.dart b/flutter/lib/features/diary/presentation/widgets/diary_sheets.dart
index ffe6381..3cccc65 100644
--- a/flutter/lib/features/diary/presentation/widgets/diary_sheets.dart
+++ b/flutter/lib/features/diary/presentation/widgets/diary_sheets.dart
@@ -10,6 +10,7 @@ import 'package:tma_app/core/theme/app_typography.dart';
 import 'package:tma_app/features/diary/domain/diary.dart';
 import 'package:tma_app/features/diary/presentation/providers/diary_providers.dart';
 import 'package:tma_app/features/diary/presentation/widgets/diary_cover.dart';
+import 'package:tma_app/features/diary/presentation/widgets/diary_join.dart';
 import 'package:tma_app/features/pet/data/pet_photo_store.dart';
 import 'package:tma_app/features/pet/domain/pet.dart';
 import 'package:tma_app/features/pet/domain/pet_target.dart';
@@ -25,9 +26,6 @@ import 'package:tma_app/shared/widgets/rup_toast.dart';
 
 const double _kNormal = AppTypography.normalHeight;
 
-/// 공유 다이어리(초대·참여·멤버)는 서버가 필요해 아직 열지 않는다
-const String kSharedDiarySoon = '공유 다이어리는 곧 열릴 예정이에요';
-
 /// 표지 편집 칸 높이 (수정 시트) — 만들 때는 정사각형
 const double _kEditCoverHeight = 150;
 const double _kCoverRadius = 10;
@@ -135,7 +133,7 @@ Future<void> showAddDiarySheet(BuildContext context, WidgetRef ref) {
           description: '초대 코드로 함께 쓰는 다이어리에 참여해요',
           onTap: () {
             Navigator.of(sheetContext).pop();
-            ref.read(toastProvider.notifier).show(kSharedDiarySoon, icon: RupIconName.users);
+            unawaited(startJoiningDiary(context, ref));
           },
         ),
       ],
@@ -167,6 +165,7 @@ class _DiaryFormState extends ConsumerState<_DiaryForm> {
   late final List<String> _targets = [...?widget.editing?.targetIds];
   late Color _ribbon = widget.editing?.ribbon ?? kRibbonColors.first;
   late String? _cover = widget.editing?.coverPath;
+  bool _shared = false;
   bool _saving = false;
 
   bool get _editing => widget.editing != null;
@@ -203,8 +202,14 @@ class _DiaryFormState extends ConsumerState<_DiaryForm> {
           targetIds: List.of(_targets),
           ribbon: _ribbon,
           coverPath: _cover,
+          shared: _shared,
         );
-        toast.show(created == null ? '다이어리는 최대 $kMaxDiaries개까지예요' : '새 다이어리를 만들었어요',
+        toast.show(
+            created == null
+                ? '다이어리는 최대 $kMaxDiaries개까지예요'
+                : _shared
+                    ? '공유 다이어리를 만들었어요'
+                    : '새 다이어리를 만들었어요',
             icon: created == null ? RupIconName.alert : RupIconName.check);
       } else {
         await notifier.updateDiary(editing.copyWith(
@@ -270,14 +275,18 @@ class _DiaryFormState extends ConsumerState<_DiaryForm> {
                   RupSegmented<bool>(
                     options: const [(false, '개인 다이어리'), (true, '공유 다이어리')],
                     icons: const [RupIconName.user, RupIconName.users],
-                    value: false,
+                    value: _shared,
                     onChanged: (shared) {
-                      if (shared) ref.read(toastProvider.notifier).show(kSharedDiarySoon, icon: RupIconName.users);
+                      if (shared && !ref.read(diaryProvider.notifier).canShare) {
+                        ref.read(toastProvider.notifier).show(kSharedDiaryLocalOnly, icon: RupIconName.users);
+                        return;
+                      }
+                      setState(() => _shared = shared);
                     },
                   ),
                   const SizedBox(height: 7),
                   Text(
-                    '나만 기록하는 다이어리예요. 나중에 공유로 바꿀 수 있어요.',
+                    _shared ? '만든 뒤 가족·지인을 초대해 함께 기록할 수 있어요.' : '나만 기록하는 다이어리예요. 나중에 공유로 바꿀 수 있어요.',
                     style: _ui(context, 11.5, FontWeight.w400, AppColors.muted).copyWith(height: 1.45),
                   ),
                 ],
diff --git a/flutter/lib/features/diary/presentation/widgets/diary_shelf.dart b/flutter/lib/features/diary/presentation/widgets/diary_shelf.dart
index 8f243db..38a00f2 100644
--- a/flutter/lib/features/diary/presentation/widgets/diary_shelf.dart
+++ b/flutter/lib/features/diary/presentation/widgets/diary_shelf.dart
@@ -120,7 +120,7 @@ class _HomeDiaryTile extends ConsumerWidget {
   Widget build(BuildContext context, WidgetRef ref) {
     final diary = book.diary(post.diaryId);
     // 누구의 기록인지 — 다이어리의 첫 아이, 없으면 다이어리 이름
-    final who = diary == null ? '' : (diary.targetIds.map((id) => names[id]).nonNulls.firstOrNull ?? diary.name);
+    final who = diary == null ? '' : (diary.firstTargetName(names) ?? diary.name);
     final photo = post.photoPath;
     final textTheme = Theme.of(context).textTheme;
 
diff --git a/flutter/lib/features/notifications/domain/app_notice.dart b/flutter/lib/features/notifications/domain/app_notice.dart
index 84816b3..e7c2e51 100644
--- a/flutter/lib/features/notifications/domain/app_notice.dart
+++ b/flutter/lib/features/notifications/domain/app_notice.dart
@@ -22,6 +22,7 @@ class AppNotice {
     required this.at,
     required this.text,
     this.who,
+    this.whoPhotoPath,
   });
 
   final String id;
@@ -35,6 +36,9 @@ class AppNotice {
 
   /// 새 글·댓글을 남긴 사람 이름
   final String? who;
+
+  /// 그 사람의 프로필 사진
+  final String? whoPhotoPath;
 }
 
 /// 알림을 묶는 날 — 오늘 · 어제 · 최근 7일
diff --git a/flutter/lib/features/notifications/presentation/pages/notifications_page.dart b/flutter/lib/features/notifications/presentation/pages/notifications_page.dart
index c8f7920..441e280 100644
--- a/flutter/lib/features/notifications/presentation/pages/notifications_page.dart
+++ b/flutter/lib/features/notifications/presentation/pages/notifications_page.dart
@@ -3,11 +3,13 @@ import 'dart:async';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:go_router/go_router.dart';
+import 'package:tma_app/core/api/api_guard.dart';
 import 'package:tma_app/core/constants/app_colors.dart';
 import 'package:tma_app/core/constants/app_sizes.dart';
 import 'package:tma_app/core/router/app_routes.dart';
 import 'package:tma_app/core/theme/app_typography.dart';
 import 'package:tma_app/core/utils/clock.dart';
+import 'package:tma_app/features/diary/presentation/providers/diary_providers.dart';
 import 'package:tma_app/features/notifications/domain/app_notice.dart';
 import 'package:tma_app/features/notifications/presentation/providers/notice_providers.dart';
 import 'package:tma_app/shared/widgets/icons/rup_icon.dart';
@@ -37,6 +39,10 @@ class _NotificationsPageState extends ConsumerState<NotificationsPage> {
     WidgetsBinding.instance.addPostFrameCallback((_) {
       if (mounted) unawaited(ref.read(noticeSeenProvider.notifier).markSeen(ref.read(clockProvider)()));
     });
+    // 공유 다이어리가 있으면 다른 멤버의 새 글·댓글을 다시 읽는다
+    if (ref.read(diaryBookProvider).diaries.any((d) => d.shared)) {
+      unawaited(succeeded(ref.read(diaryProvider.notifier).refresh()));
+    }
   }
 
   @override
@@ -147,7 +153,7 @@ class _NoticeRow extends StatelessWidget {
             crossAxisAlignment: CrossAxisAlignment.start,
             children: [
               if (n.who != null)
-                const PersonAvatar(size: _kAvatar)
+                PersonAvatar(size: _kAvatar, photoPath: n.whoPhotoPath)
               else
                 Container(
                   width: _kAvatar,
diff --git a/flutter/lib/features/notifications/presentation/providers/notice_providers.dart b/flutter/lib/features/notifications/presentation/providers/notice_providers.dart
index f4923a2..5c634d5 100644
--- a/flutter/lib/features/notifications/presentation/providers/notice_providers.dart
+++ b/flutter/lib/features/notifications/presentation/providers/notice_providers.dart
@@ -31,8 +31,11 @@ class NoticeSeenNotifier extends Notifier<DateTime?> {
 
 final noticeSeenProvider = NotifierProvider<NoticeSeenNotifier, DateTime?>(NoticeSeenNotifier.new);
 
+/// 알림으로 보여 줄 기간 — 알림 화면은 최근 7일까지 묶어 보여 준다 ([NoticeDay])
+const Duration _kNoticeWindow = Duration(days: 7);
+
 /// 모든 다이어리의 알림 — 최근 것이 위로.
-/// 지금은 기기에서 만드는 기록 알림만 있다. 공유 다이어리의 새 글·댓글은 서버가 생기면 여기에 더한다.
+/// 기록 알림은 기기에서 만들고, 공유 다이어리의 새 글·댓글은 서버에서 읽은 기록·댓글 중 남이 쓴 것으로 만든다.
 final noticesProvider = Provider<List<AppNotice>>((ref) => _watchNotices(ref));
 
 /// 알림 목록을 알림기에서 바로 계산한다 — 파생 프로바이더끼리 잇지 않는다 ([petListProvider] 주석 참고)
@@ -50,7 +53,7 @@ List<AppNotice> _watchNotices(Ref ref) {
   if (settings[AppSetting.scheduleNotification] == false) return const [];
 
   final book = ref.watch(diaryProvider).value ?? DiaryBook.empty;
-  final notices = <AppNotice>[];
+  final notices = <AppNotice>[...diaryActivityNotices(book, watchShelf(ref), now)];
   if (now.hour >= kDiaryReminderHour) {
     final at = DateTime(now.year, now.month, now.day, kDiaryReminderHour);
     // 추억 보관함으로 간 다이어리는 알리지 않는다
@@ -69,6 +72,49 @@ List<AppNotice> _watchNotices(Ref ref) {
   return notices..sort((a, b) => b.at.compareTo(a.at));
 }
 
+/// 공유 다이어리에서 다른 멤버가 남긴 새 글 · 내 기록에 달린 댓글 (최근 7일, 다이어리별 알림 설정을 따른다)
+List<AppNotice> diaryActivityNotices(DiaryBook book, List<Diary> shelf, DateTime now) {
+  final since = now.subtract(_kNoticeWindow);
+  final shared = {for (final d in shelf.where((d) => d.shared)) d.id: d};
+  final notices = <AppNotice>[];
+  final myPosts = <String, DiaryPost>{};
+  for (final p in book.posts) {
+    final diary = shared[p.diaryId];
+    if (diary == null) continue;
+    if (p.isMine) {
+      myPosts[p.id] = p;
+      continue;
+    }
+    if (!diary.notifies(DiaryNotice.newPost) || p.createdAt.isBefore(since)) continue;
+    notices.add(AppNotice(
+      id: 'post-${p.id}',
+      type: NoticeType.newPost,
+      diaryId: diary.id,
+      diaryName: diary.name,
+      at: p.createdAt,
+      text: p.text,
+      who: p.author?.name,
+      whoPhotoPath: p.author?.photoPath,
+    ));
+  }
+  for (final c in book.comments) {
+    final post = myPosts[c.postId];
+    final diary = post == null ? null : shared[post.diaryId];
+    if (diary == null || c.isMine || !diary.notifies(DiaryNotice.newComment) || c.createdAt.isBefore(since)) continue;
+    notices.add(AppNotice(
+      id: 'comment-${c.id}',
+      type: NoticeType.newComment,
+      diaryId: diary.id,
+      diaryName: diary.name,
+      at: c.createdAt,
+      text: c.text,
+      who: c.author?.name,
+      whoPhotoPath: c.author?.photoPath,
+    ));
+  }
+  return notices;
+}
+
 /// 아직 보지 않은 알림이 있는지 — 홈 종에 점을 찍는다
 final hasUnreadNoticeProvider = Provider<bool>((ref) {
   final seen = ref.watch(noticeSeenProvider);
diff --git a/flutter/lib/features/pet_card/presentation/pages/card_scanner_page.dart b/flutter/lib/features/pet_card/presentation/pages/card_scanner_page.dart
index 5c968ae..b84fbdf 100644
--- a/flutter/lib/features/pet_card/presentation/pages/card_scanner_page.dart
+++ b/flutter/lib/features/pet_card/presentation/pages/card_scanner_page.dart
@@ -1,463 +1,30 @@
-import 'dart:async';
-import 'dart:math' as math;
-
 import 'package:flutter/material.dart';
-import 'package:flutter/services.dart';
-import 'package:flutter_riverpod/flutter_riverpod.dart';
-import 'package:go_router/go_router.dart';
-import 'package:mobile_scanner/mobile_scanner.dart';
-import 'package:tma_app/core/api/api_guard.dart';
 import 'package:tma_app/core/api/error_lexicon.dart';
-import 'package:tma_app/core/constants/app_colors.dart';
-import 'package:tma_app/core/theme/app_typography.dart';
 import 'package:tma_app/features/pet_card/domain/received_card.dart';
 import 'package:tma_app/features/pet_card/presentation/providers/received_card_providers.dart';
-import 'package:tma_app/shared/widgets/icons/rup_icon.dart';
-import 'package:tma_app/shared/widgets/pressable.dart';
-import 'package:tma_app/shared/widgets/rup_toast.dart';
+import 'package:tma_app/shared/widgets/qr_scanner_page.dart';
 
-// 시안 .rup-scanner 치수·색
-const Color _kScannerBg = Color(0xFF14110E);
-const Color _kDim = Color(0x99120F0C); // rgba(18,15,12,.6)
-const Color _kFoundGreen = Color(0xFF4ED08A);
-const double _kFrame = 244;
-const double _kFrameRadius = 22;
-const double _kCorner = 36;
-const double _kCornerStroke = 4;
-const double _kCloseSize = 38;
-const double _kCheckSize = 70;
-
-/// 스캔 줄이 위아래로 한 번 오가는 시간 (시안 2.3s)
-const Duration _kSweep = Duration(milliseconds: 1150);
-
-/// 명함을 찾은 뒤 체크 표시를 보여 주는 최소 시간 (시안 820ms)
-const Duration _kFoundHold = Duration(milliseconds: 820);
-
-/// 같은 QR 을 실패한 뒤 다시 읽기까지 기다리는 시간 — 같은 알림이 계속 뜨지 않게
-const Duration _kRetryGap = Duration(seconds: 3);
-
-/// 스캐너를 닫은 결과
-sealed class ScanOutcome {
-  const ScanOutcome();
-}
-
-/// QR 로 명함을 찾았다
-final class ScanFound extends ScanOutcome {
-  const ScanFound(this.card);
-
-  final SharedCard card;
-}
-
-/// "명함 코드 입력하기"를 눌렀다
-final class ScanTypeCode extends ScanOutcome {
-  const ScanTypeCode();
-}
-
-/// QR 을 읽어 알려 주는 카메라 화면
-typedef ScannerCamera = Widget Function(ValueChanged<String> onCode);
-
-/// 스캐너 카메라 — 테스트에서 실제 카메라 대신 끼운다 (null 이면 기기 카메라)
-final scannerCameraProvider = Provider<ScannerCamera?>((ref) => null);
+/// 명함 받기 스캐너 문구
+const QrScanCopy _kCopy = QrScanCopy(
+  title: '명함 받기',
+  hint: '상대의 펫 명함 QR 코드를\n사각형 안에 비춰주세요.',
+  foundHint: '명함을 찾았어요! 정보 불러오는 중…',
+  manualLabel: '명함 코드 입력하기',
+  unavailableHint: '카메라를 쓸 수 없어요.\n설정에서 카메라 권한을 허용하거나 명함 코드를 입력해 주세요.',
+);
 
 /// 명함 받기 스캐너 — 상대 명함의 QR 을 비추면 명함을 불러온다
-class CardScannerPage extends ConsumerStatefulWidget {
+class CardScannerPage extends StatelessWidget {
   const CardScannerPage({super.key});
 
-  @override
-  ConsumerState<CardScannerPage> createState() => _CardScannerPageState();
-}
-
-class _CardScannerPageState extends ConsumerState<CardScannerPage> {
-  late final ScannerCamera? _fakeCamera = ref.read(scannerCameraProvider);
-  MobileScannerController? _controller;
-  bool _found = false;
-  bool _busy = false;
-  String? _lastRaw;
-  DateTime _lastAt = DateTime.fromMillisecondsSinceEpoch(0);
-
-  @override
-  void initState() {
-    super.initState();
-    if (_fakeCamera == null) _controller = MobileScannerController(formats: const [BarcodeFormat.qrCode]);
-  }
-
-  @override
-  void dispose() {
-    unawaited(_controller?.dispose());
-    // 다른 화면은 상태 표시줄 모양을 따로 정하지 않는다 — 어두운 글자(앱 기본)로 되돌린다
-    SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle.dark);
-    super.dispose();
-  }
-
-  void _onDetect(BarcodeCapture capture) {
-    final raw = capture.barcodes.map((b) => b.rawValue).nonNulls.firstOrNull;
-    if (raw != null) unawaited(_onCode(raw));
-  }
-
-  Future<void> _onCode(String raw) async {
-    if (_busy) return;
-    final now = DateTime.now();
-    if (raw == _lastRaw && now.difference(_lastAt) < _kRetryGap) return;
-    _lastRaw = raw;
-    _lastAt = now;
-
-    final code = parseCardCode(raw);
-    if (code == null) {
-      // 펫 명함 QR 이 아니다 — 서버가 못 찾았을 때와 같은 안내
-      ref.read(toastProvider.notifier).show(ErrorLexicon.getMessage('CARD_002'), icon: RupIconName.alert);
-      return;
-    }
-    _busy = true;
-    setState(() => _found = true);
-    final shown = Stopwatch()..start();
-    try {
-      final card = await ref.read(receivedCardsProvider.notifier).preview(code);
-      final rest = _kFoundHold - shown.elapsed;
-      if (rest > Duration.zero) await Future<void>.delayed(rest);
-      if (mounted) context.pop(ScanFound(card));
-    } catch (e) {
-      if (!isReportedApiFailure(e)) rethrow;
-      // 실패 알림은 인터셉터가 띄웠다 — 다시 비출 수 있게 되돌린다
-      _lastAt = DateTime.now();
-      if (mounted) {
-        setState(() {
-          _found = false;
-          _busy = false;
-        });
-      }
-    }
-  }
-
-  Widget _camera() {
-    final camera = _fakeCamera;
-    if (camera != null) return camera(_onCode);
-    return MobileScanner(
-      controller: _controller,
-      onDetect: _onDetect,
-      // 카메라를 켜는 동안·쓸 수 없을 때는 시안의 어두운 바탕 (안내는 아래 문구가 맡는다)
-      placeholderBuilder: (context) => const _Feed(),
-      errorBuilder: (context, error) => const _Feed(),
-    );
-  }
-
   @override
   Widget build(BuildContext context) {
-    final top = MediaQuery.paddingOf(context).top;
-    final topBarHeight = top + 8 + _kCloseSize;
-    return AnnotatedRegion<SystemUiOverlayStyle>(
-      value: SystemUiOverlayStyle.light,
-      child: Scaffold(
-        backgroundColor: _kScannerBg,
-        body: Stack(
-          children: [
-            Positioned.fill(child: _camera()),
-            Positioned.fill(
-              child: Column(
-                children: [
-                  SizedBox(height: topBarHeight),
-                  Expanded(
-                    child: Center(
-                      child: _Frame(found: _found),
-                    ),
-                  ),
-                  _Bottom(
-                    found: _found,
-                    camera: _controller,
-                    onManual: () => context.pop(const ScanTypeCode()),
-                  ),
-                ],
-              ),
-            ),
-            // 조준 프레임 바깥을 어둡게 덮는 막이 위 막대를 가리지 않게 맨 위에 둔다
-            Positioned(
-              top: top + 8,
-              left: 18,
-              right: 18,
-              child: _TopBar(onClose: () => context.pop()),
-            ),
-          ],
-        ),
-      ),
-    );
-  }
-}
-
-/// 카메라 화면이 아직 없을 때의 바탕 (시안 .rup-scanner__feed)
-class _Feed extends StatelessWidget {
-  const _Feed();
-
-  @override
-  Widget build(BuildContext context) {
-    return const DecoratedBox(
-      decoration: BoxDecoration(
-        gradient: RadialGradient(
-          center: Alignment(0, -.2),
-          radius: 1.1,
-          colors: [Color(0xFF3A332B), Color(0xFF221D17), _kScannerBg],
-          stops: [0, .56, 1],
-        ),
-      ),
-    );
-  }
-}
-
-class _TopBar extends StatelessWidget {
-  const _TopBar({required this.onClose});
-
-  final VoidCallback onClose;
-
-  @override
-  Widget build(BuildContext context) {
-    return Row(
-      children: [
-        Semantics(
-          button: true,
-          label: '닫기',
-          child: Pressable(
-            pressedScale: .9,
-            onTap: onClose,
-            child: Container(
-              width: _kCloseSize,
-              height: _kCloseSize,
-              decoration: const BoxDecoration(color: Color(0x24FFFFFF), shape: BoxShape.circle),
-              alignment: Alignment.center,
-              child: const RupIcon(RupIconName.x, size: 20, stroke: 2.4, color: Colors.white),
-            ),
-          ),
-        ),
-        const Expanded(
-          child: Text(
-            '명함 받기',
-            textAlign: TextAlign.center,
-            style: TextStyle(
-              fontFamily: AppFonts.display,
-              fontSize: 16,
-              fontWeight: FontWeight.w800,
-              height: AppTypography.displayNormalHeight,
-              color: Colors.white,
-            ),
-          ),
-        ),
-        const SizedBox(width: _kCloseSize),
-      ],
-    );
-  }
-}
-
-/// 조준 프레임 — 바깥은 어둡게, 모서리 표시 + 스캔 줄, 찾으면 초록 체크
-class _Frame extends StatefulWidget {
-  const _Frame({required this.found});
-
-  final bool found;
-
-  @override
-  State<_Frame> createState() => _FrameState();
-}
-
-class _FrameState extends State<_Frame> with SingleTickerProviderStateMixin {
-  late final AnimationController _sweep = AnimationController(vsync: this, duration: _kSweep)
-    ..repeat(reverse: true);
-
-  @override
-  void dispose() {
-    _sweep.dispose();
-    super.dispose();
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    final found = widget.found;
-    return SizedBox.square(
-      dimension: _kFrame,
-      child: CustomPaint(
-        painter: const _DimOutside(),
-        child: Stack(
-          clipBehavior: Clip.none,
-          children: [
-            Positioned.fill(
-              child: TweenAnimationBuilder<Color?>(
-                tween: ColorTween(end: found ? _kFoundGreen : AppColors.primary),
-                duration: const Duration(milliseconds: 300),
-                builder: (context, color, _) => CustomPaint(painter: _Corners(color ?? AppColors.primary)),
-              ),
-            ),
-            if (!found)
-              AnimatedBuilder(
-                animation: _sweep,
-                builder: (context, child) {
-                  final t = Curves.easeInOut.transform(_sweep.value);
-                  return Positioned(left: 10, right: 10, top: 12 + (_kFrame - 28) * t, child: child!);
-                },
-                child: Container(
-                  height: 2,
-                  decoration: const BoxDecoration(
-                    gradient: LinearGradient(colors: [Color(0x00FF7500), AppColors.primary, Color(0x00FF7500)]),
-                    boxShadow: [BoxShadow(color: Color(0xB3FF7500), blurRadius: 14, spreadRadius: 2)],
-                  ),
-                ),
-              ),
-            Center(
-              child: AnimatedOpacity(
-                duration: const Duration(milliseconds: 250),
-                opacity: found ? 1 : 0,
-                child: AnimatedScale(
-                  duration: const Duration(milliseconds: 400),
-                  curve: const Cubic(.34, 1.5, .5, 1),
-                  scale: found ? 1 : .5,
-                  child: Container(
-                    width: _kCheckSize,
-                    height: _kCheckSize,
-                    decoration: const BoxDecoration(
-                      color: _kFoundGreen,
-                      shape: BoxShape.circle,
-                      boxShadow: [BoxShadow(color: Color(0x804ED08A), offset: Offset(0, 10), blurRadius: 30)],
-                    ),
-                    alignment: Alignment.center,
-                    child: const RupIcon(RupIconName.check, size: 36, stroke: 3, color: Colors.white),
-                  ),
-                ),
-              ),
-            ),
-          ],
-        ),
-      ),
-    );
-  }
-}
-
-/// 프레임 바깥 화면 전체를 어둡게 (시안 box-shadow 0 0 0 2000px)
-class _DimOutside extends CustomPainter {
-  const _DimOutside();
-
-  @override
-  void paint(Canvas canvas, Size size) {
-    const reach = 4000.0;
-    final outside = Path()
-      ..fillType = PathFillType.evenOdd
-      ..addRect(Rect.fromLTRB(-reach, -reach, size.width + reach, size.height + reach))
-      ..addRRect(RRect.fromRectAndRadius(Offset.zero & size, const Radius.circular(_kFrameRadius)));
-    canvas.drawPath(outside, Paint()..color = _kDim);
-  }
-
-  @override
-  bool shouldRepaint(_DimOutside oldDelegate) => false;
-}
-
-/// 네 모서리 표시 — 프레임 테두리를 따라 굵기 4, 길이 36
-class _Corners extends CustomPainter {
-  const _Corners(this.color);
-
-  final Color color;
-
-  @override
-  void paint(Canvas canvas, Size size) {
-    final paint = Paint()
-      ..color = color
-      ..style = PaintingStyle.stroke
-      ..strokeWidth = _kCornerStroke
-      ..strokeCap = StrokeCap.butt;
-    const r = 16.0; // 시안 바깥 반경 18 − 굵기 절반
-    const reach = _kCorner - _kCornerStroke / 2;
-    final w = size.width;
-    final h = size.height;
-    final rect = Rect.fromCircle(center: Offset.zero, radius: r);
-    final corners = <(Offset, double)>[
-      (Offset.zero, math.pi), // 왼쪽 위
-      (Offset(w, 0), -math.pi / 2), // 오른쪽 위
-      (Offset(w, h), 0), // 오른쪽 아래
-      (Offset(0, h), math.pi / 2), // 왼쪽 아래
-    ];
-    for (final (corner, start) in corners) {
-      // 모서리를 원점으로 옮겨 같은 모양(가로·세로 직선 + 사분원)을 돌려 그린다
-      canvas
-        ..save()
-        ..translate(corner.dx, corner.dy)
-        ..rotate(start - math.pi);
-      final path = Path()
-        ..moveTo(0, reach)
-        ..lineTo(0, r)
-        ..arcTo(rect.shift(const Offset(r, r)), math.pi, math.pi / 2, false)
-        ..lineTo(reach, 0);
-      canvas
-        ..drawPath(path, paint)
-        ..restore();
-    }
-  }
-
-  @override
-  bool shouldRepaint(_Corners oldDelegate) => oldDelegate.color != color;
-}
-
-/// 안내 문구 + "명함 코드 입력하기"
-class _Bottom extends StatelessWidget {
-  const _Bottom({required this.found, required this.camera, required this.onManual});
-
-  final bool found;
-
-  /// 카메라 상태 — 쓸 수 없으면 안내 문구를 바꾼다 (테스트 카메라면 null)
-  final MobileScannerController? camera;
-  final VoidCallback onManual;
-
-  @override
-  Widget build(BuildContext context) {
-    final camera = this.camera;
-    final hint = camera == null
-        ? _hint(found: found, unavailable: false)
-        : ValueListenableBuilder<MobileScannerState>(
-            valueListenable: camera,
-            builder: (context, state, _) => _hint(found: found, unavailable: state.error != null),
-          );
-    return Padding(
-      padding: EdgeInsets.fromLTRB(24, 0, 24, math.max(MediaQuery.paddingOf(context).bottom + 96, 150)),
-      child: Column(
-        mainAxisSize: MainAxisSize.min,
-        children: [
-          hint,
-          // 찾은 뒤에는 버튼을 숨기되 자리는 지켜 프레임이 움직이지 않게 한다
-          Visibility.maintain(
-            visible: !found,
-            child: Padding(
-              padding: const EdgeInsets.only(top: 22),
-              child: Pressable(
-                pressedScale: .96,
-                onTap: onManual,
-                child: Container(
-                  padding: const EdgeInsets.symmetric(horizontal: 30, vertical: 15),
-                  decoration: BoxDecoration(
-                    color: const Color(0x33FF7500),
-                    borderRadius: BorderRadius.circular(999),
-                    border: Border.all(color: const Color(0x9EFF963C), width: 1.5),
-                    boxShadow: const [BoxShadow(color: Color(0x38FF7500), offset: Offset(0, 4), blurRadius: 18)],
-                  ),
-                  child: const Text(
-                    '명함 코드 입력하기',
-                    style: TextStyle(
-                      fontFamily: AppFonts.display,
-                      fontSize: 15.5,
-                      fontWeight: FontWeight.w800,
-                      height: AppTypography.displayNormalHeight,
-                      color: Colors.white,
-                    ),
-                  ),
-                ),
-              ),
-            ),
-          ),
-        ],
-      ),
-    );
-  }
-
-  Widget _hint({required bool found, required bool unavailable}) {
-    final text = found
-        ? '명함을 찾았어요! 정보 불러오는 중…'
-        : unavailable
-            ? '카메라를 쓸 수 없어요.\n설정에서 카메라 권한을 허용하거나 명함 코드를 입력해 주세요.'
-            : '상대의 펫 명함 QR 코드를\n사각형 안에 비춰주세요.';
-    return Text(
-      text,
-      textAlign: TextAlign.center,
-      style: const TextStyle(fontSize: 13.5, height: 1.55, color: Color(0xD1FFFFFF)),
+    return QrScannerPage<SharedCard>(
+      copy: _kCopy,
+      parse: parseCardCode,
+      // 펫 명함 QR 이 아니면 서버가 못 찾았을 때와 같은 안내
+      invalidMessage: ErrorLexicon.getMessage('CARD_002'),
+      load: (ref, code) => ref.read(receivedCardsProvider.notifier).preview(code),
     );
   }
 }
diff --git a/flutter/lib/features/pet_card/presentation/pages/receive_card_page.dart b/flutter/lib/features/pet_card/presentation/pages/receive_card_page.dart
index f6d639f..cd90f44 100644
--- a/flutter/lib/features/pet_card/presentation/pages/receive_card_page.dart
+++ b/flutter/lib/features/pet_card/presentation/pages/receive_card_page.dart
@@ -10,12 +10,12 @@ import 'package:tma_app/core/constants/app_sizes.dart';
 import 'package:tma_app/core/router/app_routes.dart';
 import 'package:tma_app/core/theme/app_typography.dart';
 import 'package:tma_app/features/pet_card/domain/received_card.dart';
-import 'package:tma_app/features/pet_card/presentation/pages/card_scanner_page.dart';
 import 'package:tma_app/features/pet_card/presentation/providers/received_card_providers.dart';
 import 'package:tma_app/features/pet_card/presentation/widgets/card_code_sheet.dart';
 import 'package:tma_app/features/pet_card/presentation/widgets/name_card.dart';
 import 'package:tma_app/features/pet_card/presentation/widgets/received_card_info.dart';
 import 'package:tma_app/shared/widgets/icons/rup_icon.dart';
+import 'package:tma_app/shared/widgets/qr_scanner_page.dart';
 import 'package:tma_app/shared/widgets/rup_button.dart';
 import 'package:tma_app/shared/widgets/rup_toast.dart';
 import 'package:tma_app/shared/widgets/section_title.dart';
@@ -26,10 +26,10 @@ Future<void> startReceivingCard(BuildContext context, WidgetRef ref) async {
     ref.read(toastProvider.notifier).show('기기 저장 모드에서는 명함을 받을 수 없어요', icon: RupIconName.qrcode);
     return;
   }
-  final outcome = await context.push<ScanOutcome>(AppRoutes.petCardScan);
+  final outcome = await context.push<ScanOutcome<SharedCard>>(AppRoutes.petCardScan);
   if (!context.mounted) return;
   final card = switch (outcome) {
-    ScanFound(:final card) => card,
+    ScanFound(:final value) => value,
     ScanTypeCode() => await showCardCodeSheet(context),
     null => null,
   };
diff --git a/flutter/lib/shared/widgets/qr_scanner_page.dart b/flutter/lib/shared/widgets/qr_scanner_page.dart
new file mode 100644
index 0000000..edb708c
--- /dev/null
+++ b/flutter/lib/shared/widgets/qr_scanner_page.dart
@@ -0,0 +1,502 @@
+import 'dart:async';
+import 'dart:math' as math;
+
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:go_router/go_router.dart';
+import 'package:mobile_scanner/mobile_scanner.dart';
+import 'package:tma_app/core/api/api_guard.dart';
+import 'package:tma_app/core/constants/app_colors.dart';
+import 'package:tma_app/core/theme/app_typography.dart';
+import 'package:tma_app/shared/widgets/icons/rup_icon.dart';
+import 'package:tma_app/shared/widgets/pressable.dart';
+import 'package:tma_app/shared/widgets/rup_toast.dart';
+
+// 시안 .rup-scanner 치수·색
+const Color _kScannerBg = Color(0xFF14110E);
+const Color _kDim = Color(0x99120F0C); // rgba(18,15,12,.6)
+const Color _kFoundGreen = Color(0xFF4ED08A);
+const double _kFrame = 244;
+const double _kFrameRadius = 22;
+const double _kCorner = 36;
+const double _kCornerStroke = 4;
+const double _kCloseSize = 38;
+const double _kCheckSize = 70;
+
+/// 스캔 줄이 위아래로 한 번 오가는 시간 (시안 2.3s)
+const Duration _kSweep = Duration(milliseconds: 1150);
+
+/// 찾은 뒤 체크 표시를 보여 주는 최소 시간 (시안 820ms)
+const Duration _kFoundHold = Duration(milliseconds: 820);
+
+/// 같은 QR 을 실패한 뒤 다시 읽기까지 기다리는 시간 — 같은 알림이 계속 뜨지 않게
+const Duration _kRetryGap = Duration(seconds: 3);
+
+/// 스캐너를 닫은 결과
+sealed class ScanOutcome<T> {
+  const ScanOutcome();
+}
+
+/// QR 로 찾았다
+final class ScanFound<T> extends ScanOutcome<T> {
+  const ScanFound(this.value);
+
+  final T value;
+}
+
+/// "코드 입력하기"를 눌렀다 — 부른 화면이 입력 시트를 연다
+final class ScanTypeCode<T> extends ScanOutcome<T> {
+  const ScanTypeCode();
+}
+
+/// 스캐너 문구 — 명함 받기 · 공유 다이어리 참여
+class QrScanCopy {
+  const QrScanCopy({
+    required this.title,
+    required this.hint,
+    required this.foundHint,
+    required this.manualLabel,
+    required this.unavailableHint,
+  });
+
+  final String title;
+
+  /// 비출 때 안내 (줄바꿈 포함)
+  final String hint;
+
+  /// 찾았을 때 안내
+  final String foundHint;
+
+  /// 아래 버튼 — 코드를 직접 입력하러 간다
+  final String manualLabel;
+
+  /// 카메라를 쓸 수 없을 때 안내
+  final String unavailableHint;
+}
+
+/// QR 을 읽어 알려 주는 카메라 화면
+typedef ScannerCamera = Widget Function(ValueChanged<String> onCode);
+
+/// 스캐너 카메라 — 테스트에서 실제 카메라 대신 끼운다 (null 이면 기기 카메라)
+final scannerCameraProvider = Provider<ScannerCamera?>((ref) => null);
+
+/// QR 스캐너 — 비춘 값이 찾는 코드면 [load] 로 불러와 [ScanFound] 로 닫는다.
+/// 코드가 아니면 [invalidMessage] 를 알리고 계속 비춘다. 불러오기에 실패하면(인터셉터가 알림) 다시 비출 수 있다.
+class QrScannerPage<T> extends ConsumerStatefulWidget {
+  const QrScannerPage({
+    super.key,
+    required this.copy,
+    required this.parse,
+    required this.invalidMessage,
+    required this.load,
+  });
+
+  final QrScanCopy copy;
+
+  /// 읽은 값 → 코드 (찾는 QR 이 아니면 null)
+  final String? Function(String raw) parse;
+  final String invalidMessage;
+  final Future<T> Function(WidgetRef ref, String code) load;
+
+  @override
+  ConsumerState<QrScannerPage<T>> createState() => _QrScannerPageState<T>();
+}
+
+class _QrScannerPageState<T> extends ConsumerState<QrScannerPage<T>> {
+  late final ScannerCamera? _fakeCamera = ref.read(scannerCameraProvider);
+  MobileScannerController? _controller;
+  bool _found = false;
+  bool _busy = false;
+  String? _lastRaw;
+  DateTime _lastAt = DateTime.fromMillisecondsSinceEpoch(0);
+
+  @override
+  void initState() {
+    super.initState();
+    if (_fakeCamera == null) _controller = MobileScannerController(formats: const [BarcodeFormat.qrCode]);
+  }
+
+  @override
+  void dispose() {
+    unawaited(_controller?.dispose());
+    // 다른 화면은 상태 표시줄 모양을 따로 정하지 않는다 — 어두운 글자(앱 기본)로 되돌린다
+    SystemChrome.setSystemUIOverlayStyle(SystemUiOverlayStyle.dark);
+    super.dispose();
+  }
+
+  void _onDetect(BarcodeCapture capture) {
+    final raw = capture.barcodes.map((b) => b.rawValue).nonNulls.firstOrNull;
+    if (raw != null) unawaited(_onCode(raw));
+  }
+
+  Future<void> _onCode(String raw) async {
+    if (_busy) return;
+    final now = DateTime.now();
+    if (raw == _lastRaw && now.difference(_lastAt) < _kRetryGap) return;
+    _lastRaw = raw;
+    _lastAt = now;
+
+    final code = widget.parse(raw);
+    if (code == null) {
+      // 찾는 QR 이 아니다
+      ref.read(toastProvider.notifier).show(widget.invalidMessage, icon: RupIconName.alert);
+      return;
+    }
+    _busy = true;
+    setState(() => _found = true);
+    final shown = Stopwatch()..start();
+    try {
+      final value = await widget.load(ref, code);
+      final rest = _kFoundHold - shown.elapsed;
+      if (rest > Duration.zero) await Future<void>.delayed(rest);
+      if (mounted) context.pop(ScanFound<T>(value));
+    } catch (e) {
+      if (!isReportedApiFailure(e)) rethrow;
+      // 실패 알림은 인터셉터가 띄웠다 — 다시 비출 수 있게 되돌린다
+      _lastAt = DateTime.now();
+      if (mounted) {
+        setState(() {
+          _found = false;
+          _busy = false;
+        });
+      }
+    }
+  }
+
+  Widget _camera() {
+    final camera = _fakeCamera;
+    if (camera != null) return camera(_onCode);
+    return MobileScanner(
+      controller: _controller,
+      onDetect: _onDetect,
+      // 카메라를 켜는 동안·쓸 수 없을 때는 시안의 어두운 바탕 (안내는 아래 문구가 맡는다)
+      placeholderBuilder: (context) => const _Feed(),
+      errorBuilder: (context, error) => const _Feed(),
+    );
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final top = MediaQuery.paddingOf(context).top;
+    final topBarHeight = top + 8 + _kCloseSize;
+    return AnnotatedRegion<SystemUiOverlayStyle>(
+      value: SystemUiOverlayStyle.light,
+      child: Scaffold(
+        backgroundColor: _kScannerBg,
+        body: Stack(
+          children: [
+            Positioned.fill(child: _camera()),
+            Positioned.fill(
+              child: Column(
+                children: [
+                  SizedBox(height: topBarHeight),
+                  Expanded(
+                    child: Center(
+                      child: _Frame(found: _found),
+                    ),
+                  ),
+                  _Bottom(
+                    copy: widget.copy,
+                    found: _found,
+                    camera: _controller,
+                    onManual: () => context.pop(ScanTypeCode<T>()),
+                  ),
+                ],
+              ),
+            ),
+            // 조준 프레임 바깥을 어둡게 덮는 막이 위 막대를 가리지 않게 맨 위에 둔다
+            Positioned(
+              top: top + 8,
+              left: 18,
+              right: 18,
+              child: _TopBar(title: widget.copy.title, onClose: () => context.pop()),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+/// 카메라 화면이 아직 없을 때의 바탕 (시안 .rup-scanner__feed)
+class _Feed extends StatelessWidget {
+  const _Feed();
+
+  @override
+  Widget build(BuildContext context) {
+    return const DecoratedBox(
+      decoration: BoxDecoration(
+        gradient: RadialGradient(
+          center: Alignment(0, -.2),
+          radius: 1.1,
+          colors: [Color(0xFF3A332B), Color(0xFF221D17), _kScannerBg],
+          stops: [0, .56, 1],
+        ),
+      ),
+    );
+  }
+}
+
+class _TopBar extends StatelessWidget {
+  const _TopBar({required this.title, required this.onClose});
+
+  final String title;
+  final VoidCallback onClose;
+
+  @override
+  Widget build(BuildContext context) {
+    return Row(
+      children: [
+        Semantics(
+          button: true,
+          label: '닫기',
+          child: Pressable(
+            pressedScale: .9,
+            onTap: onClose,
+            child: Container(
+              width: _kCloseSize,
+              height: _kCloseSize,
+              decoration: const BoxDecoration(color: Color(0x24FFFFFF), shape: BoxShape.circle),
+              alignment: Alignment.center,
+              child: const RupIcon(RupIconName.x, size: 20, stroke: 2.4, color: Colors.white),
+            ),
+          ),
+        ),
+        Expanded(
+          child: Text(
+            title,
+            textAlign: TextAlign.center,
+            style: const TextStyle(
+              fontFamily: AppFonts.display,
+              fontSize: 16,
+              fontWeight: FontWeight.w800,
+              height: AppTypography.displayNormalHeight,
+              color: Colors.white,
+            ),
+          ),
+        ),
+        const SizedBox(width: _kCloseSize),
+      ],
+    );
+  }
+}
+
+/// 조준 프레임 — 바깥은 어둡게, 모서리 표시 + 스캔 줄, 찾으면 초록 체크
+class _Frame extends StatefulWidget {
+  const _Frame({required this.found});
+
+  final bool found;
+
+  @override
+  State<_Frame> createState() => _FrameState();
+}
+
+class _FrameState extends State<_Frame> with SingleTickerProviderStateMixin {
+  late final AnimationController _sweep = AnimationController(vsync: this, duration: _kSweep)
+    ..repeat(reverse: true);
+
+  @override
+  void dispose() {
+    _sweep.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final found = widget.found;
+    return SizedBox.square(
+      dimension: _kFrame,
+      child: CustomPaint(
+        painter: const _DimOutside(),
+        child: Stack(
+          clipBehavior: Clip.none,
+          children: [
+            Positioned.fill(
+              child: TweenAnimationBuilder<Color?>(
+                tween: ColorTween(end: found ? _kFoundGreen : AppColors.primary),
+                duration: const Duration(milliseconds: 300),
+                builder: (context, color, _) => CustomPaint(painter: _Corners(color ?? AppColors.primary)),
+              ),
+            ),
+            if (!found)
+              AnimatedBuilder(
+                animation: _sweep,
+                builder: (context, child) {
+                  final t = Curves.easeInOut.transform(_sweep.value);
+                  return Positioned(left: 10, right: 10, top: 12 + (_kFrame - 28) * t, child: child!);
+                },
+                child: Container(
+                  height: 2,
+                  decoration: const BoxDecoration(
+                    gradient: LinearGradient(colors: [Color(0x00FF7500), AppColors.primary, Color(0x00FF7500)]),
+                    boxShadow: [BoxShadow(color: Color(0xB3FF7500), blurRadius: 14, spreadRadius: 2)],
+                  ),
+                ),
+              ),
+            Center(
+              child: AnimatedOpacity(
+                duration: const Duration(milliseconds: 250),
+                opacity: found ? 1 : 0,
+                child: AnimatedScale(
+                  duration: const Duration(milliseconds: 400),
+                  curve: const Cubic(.34, 1.5, .5, 1),
+                  scale: found ? 1 : .5,
+                  child: Container(
+                    width: _kCheckSize,
+                    height: _kCheckSize,
+                    decoration: const BoxDecoration(
+                      color: _kFoundGreen,
+                      shape: BoxShape.circle,
+                      boxShadow: [BoxShadow(color: Color(0x804ED08A), offset: Offset(0, 10), blurRadius: 30)],
+                    ),
+                    alignment: Alignment.center,
+                    child: const RupIcon(RupIconName.check, size: 36, stroke: 3, color: Colors.white),
+                  ),
+                ),
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+/// 프레임 바깥 화면 전체를 어둡게 (시안 box-shadow 0 0 0 2000px)
+class _DimOutside extends CustomPainter {
+  const _DimOutside();
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    const reach = 4000.0;
+    final outside = Path()
+      ..fillType = PathFillType.evenOdd
+      ..addRect(Rect.fromLTRB(-reach, -reach, size.width + reach, size.height + reach))
+      ..addRRect(RRect.fromRectAndRadius(Offset.zero & size, const Radius.circular(_kFrameRadius)));
+    canvas.drawPath(outside, Paint()..color = _kDim);
+  }
+
+  @override
+  bool shouldRepaint(_DimOutside oldDelegate) => false;
+}
+
+/// 네 모서리 표시 — 프레임 테두리를 따라 굵기 4, 길이 36
+class _Corners extends CustomPainter {
+  const _Corners(this.color);
+
+  final Color color;
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    final paint = Paint()
+      ..color = color
+      ..style = PaintingStyle.stroke
+      ..strokeWidth = _kCornerStroke
+      ..strokeCap = StrokeCap.butt;
+    const r = 16.0; // 시안 바깥 반경 18 − 굵기 절반
+    const reach = _kCorner - _kCornerStroke / 2;
+    final w = size.width;
+    final h = size.height;
+    final rect = Rect.fromCircle(center: Offset.zero, radius: r);
+    final corners = <(Offset, double)>[
+      (Offset.zero, math.pi), // 왼쪽 위
+      (Offset(w, 0), -math.pi / 2), // 오른쪽 위
+      (Offset(w, h), 0), // 오른쪽 아래
+      (Offset(0, h), math.pi / 2), // 왼쪽 아래
+    ];
+    for (final (corner, start) in corners) {
+      // 모서리를 원점으로 옮겨 같은 모양(가로·세로 직선 + 사분원)을 돌려 그린다
+      canvas
+        ..save()
+        ..translate(corner.dx, corner.dy)
+        ..rotate(start - math.pi);
+      final path = Path()
+        ..moveTo(0, reach)
+        ..lineTo(0, r)
+        ..arcTo(rect.shift(const Offset(r, r)), math.pi, math.pi / 2, false)
+        ..lineTo(reach, 0);
+      canvas
+        ..drawPath(path, paint)
+        ..restore();
+    }
+  }
+
+  @override
+  bool shouldRepaint(_Corners oldDelegate) => oldDelegate.color != color;
+}
+
+/// 안내 문구 + "코드 입력하기"
+class _Bottom extends StatelessWidget {
+  const _Bottom({required this.copy, required this.found, required this.camera, required this.onManual});
+
+  final QrScanCopy copy;
+  final bool found;
+
+  /// 카메라 상태 — 쓸 수 없으면 안내 문구를 바꾼다 (테스트 카메라면 null)
+  final MobileScannerController? camera;
+  final VoidCallback onManual;
+
+  @override
+  Widget build(BuildContext context) {
+    final camera = this.camera;
+    final hint = camera == null
+        ? _hint(found: found, unavailable: false)
+        : ValueListenableBuilder<MobileScannerState>(
+            valueListenable: camera,
+            builder: (context, state, _) => _hint(found: found, unavailable: state.error != null),
+          );
+    return Padding(
+      padding: EdgeInsets.fromLTRB(24, 0, 24, math.max(MediaQuery.paddingOf(context).bottom + 96, 150)),
+      child: Column(
+        mainAxisSize: MainAxisSize.min,
+        children: [
+          hint,
+          // 찾은 뒤에는 버튼을 숨기되 자리는 지켜 프레임이 움직이지 않게 한다
+          Visibility.maintain(
+            visible: !found,
+            child: Padding(
+              padding: const EdgeInsets.only(top: 22),
+              child: Pressable(
+                pressedScale: .96,
+                onTap: onManual,
+                child: Container(
+                  padding: const EdgeInsets.symmetric(horizontal: 30, vertical: 15),
+                  decoration: BoxDecoration(
+                    color: const Color(0x33FF7500),
+                    borderRadius: BorderRadius.circular(999),
+                    border: Border.all(color: const Color(0x9EFF963C), width: 1.5),
+                    boxShadow: const [BoxShadow(color: Color(0x38FF7500), offset: Offset(0, 4), blurRadius: 18)],
+                  ),
+                  child: Text(
+                    copy.manualLabel,
+                    style: const TextStyle(
+                      fontFamily: AppFonts.display,
+                      fontSize: 15.5,
+                      fontWeight: FontWeight.w800,
+                      height: AppTypography.displayNormalHeight,
+                      color: Colors.white,
+                    ),
+                  ),
+                ),
+              ),
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _hint({required bool found, required bool unavailable}) {
+    final text = found
+        ? copy.foundHint
+        : unavailable
+            ? copy.unavailableHint
+            : copy.hint;
+    return Text(
+      text,
+      textAlign: TextAlign.center,
+      style: const TextStyle(fontSize: 13.5, height: 1.55, color: Color(0xD1FFFFFF)),
+    );
+  }
+}
diff --git a/flutter/lib/shared/widgets/rup_button.dart b/flutter/lib/shared/widgets/rup_button.dart
index b49470c..e794fca 100644
--- a/flutter/lib/shared/widgets/rup_button.dart
+++ b/flutter/lib/shared/widgets/rup_button.dart
@@ -106,6 +106,7 @@ class RupButton extends StatelessWidget {
     this.dimmedOpacity = .5,
     this.height,
     this.leading,
+    this.foreground,
   });
 
   final String label;
@@ -131,9 +132,12 @@ class RupButton extends StatelessWidget {
   final double? height;
   final Widget? leading;
 
+  /// 글자색을 바꿀 때 — 흰 버튼의 붉은 "다이어리 나가기" 등
+  final Color? foreground;
+
   @override
   Widget build(BuildContext context) {
-    final (bg, fg, border) = switch (variant) {
+    final (bg, variantFg, border) = switch (variant) {
       RupButtonVariant.primary => (
           AppColors.primary,
           Colors.white,
@@ -150,6 +154,7 @@ class RupButton extends StatelessWidget {
       RupButtonVariant.light => (AppColors.offWhite, AppColors.ink, null),
       RupButtonVariant.memory => (AppColors.memory, Colors.white, AppColors.memory),
     };
+    final fg = foreground ?? variantFg;
     final size = large ? _kFontSizeLarge : _kFontSize;
     final textStyle = variant == RupButtonVariant.light
         ? Theme.of(context).textTheme.labelLarge!.copyWith(color: fg, fontSize: size)
diff --git a/flutter/lib/shared/widgets/rup_dialog.dart b/flutter/lib/shared/widgets/rup_dialog.dart
index 2a64a00..cea0bac 100644
--- a/flutter/lib/shared/widgets/rup_dialog.dart
+++ b/flutter/lib/shared/widgets/rup_dialog.dart
@@ -34,6 +34,8 @@ Future<bool> showRupConfirm(
   Color? iconBackground,
   RupButtonVariant? confirmVariant,
   bool tightTop = false,
+  Widget? leading,
+  InlineSpan? titleSpan,
 }) async {
   final result = await showBlurredDialog<bool>(
     context,
@@ -60,7 +62,13 @@ Future<bool> showRupConfirm(
               children: [
                 // 시안 row 확인창은 아이콘·제목 위에 4 를 둔다 (댓글 삭제처럼 없는 곳은 tightTop)
                 if (row && !tightTop) const SizedBox(height: AppSpacing.xs),
-                if (icon != null || glyph != null)
+                // 아이콘 상자 대신 그릴 것 — 멤버를 내보낼 때의 사람 사진 등
+                if (leading != null)
+                  Padding(
+                    padding: const EdgeInsets.only(bottom: AppSpacing.md),
+                    child: Center(child: leading),
+                  )
+                else if (icon != null || glyph != null)
                   Center(
                     child: Container(
                       width: 54,
@@ -76,8 +84,9 @@ Future<bool> showRupConfirm(
                           : RupIcon(icon!, size: 26, stroke: 2, color: iconColor),
                     ),
                   ),
-                Text(
-                  title,
+                Text.rich(
+                  // 제목 일부에 색을 줄 때 (참여할 다이어리 이름 등)
+                  titleSpan ?? TextSpan(text: title),
                   textAlign: TextAlign.center,
                   style: row
                       ? textTheme.titleSmall!.copyWith(fontSize: 16.5, fontWeight: FontWeight.w800)
diff --git a/flutter/test/api_diary_repository_test.dart b/flutter/test/api_diary_repository_test.dart
index 40b6ea1..04be3a5 100644
--- a/flutter/test/api_diary_repository_test.dart
+++ b/flutter/test/api_diary_repository_test.dart
@@ -4,6 +4,7 @@ import 'package:flutter_test/flutter_test.dart';
 import 'package:tma_app/core/api/file_uploader.dart';
 import 'package:tma_app/features/diary/data/api_diary_repository.dart';
 import 'package:tma_app/features/diary/domain/diary.dart';
+import 'package:tma_app/features/diary/domain/diary_invitation.dart';
 import 'package:tma_app/features/diary/domain/mood.dart';
 
 import 'support/fake_api.dart';
@@ -113,10 +114,10 @@ void main() {
     expect(api.reported.single.message, isNot('서버 문구'));
   });
 
-  test('다이어리 수정은 바탕색을 보내지 않는다 (만들 때 정한 값을 유지한다)', () async {
+  test('다이어리 수정은 바탕색·알림을 보내지 않는다 (바탕색은 만들 때 정하고, 알림은 멤버마다 따로 둔다)', () async {
     api.on('PATCH', '/diaries/:id', (r) {
       expect(r.json!.containsKey('tint'), isFalse);
-      expect(r.json!['mutedNotices'], ['newComment']);
+      expect(r.json!.containsKey('mutedNotices'), isFalse);
       return ok(_diaryJson());
     });
     final diary = Diary(
@@ -133,6 +134,155 @@ void main() {
     expect(api.sent('PATCH', '/diaries/d1'), hasLength(1));
   });
 
+  test('내 알림 설정은 멤버 알림 경로로 보낸다', () async {
+    api.on('PUT', '/diaries/:id/muted-notices', (r) {
+      expect(r.json, {
+        'mutedNotices': ['newPost'],
+      });
+      return noContent;
+    });
+
+    await repo.setMutedNotices('d1', const {DiaryNotice.newPost});
+
+    expect(api.sent('PUT', '/diaries/d1/muted-notices'), hasLength(1));
+  });
+
+  group('공유 다이어리', () {
+    Map<String, Object?> sharedJson({bool isOwner = true}) => {
+          ..._diaryJson(),
+          'shared': true,
+          'isOwner': isOwner,
+          'ownerId': isOwner ? 'me-uuid' : 'friend-uuid',
+          'inviteCode': isOwner ? 'RUP-8F3K2Q' : null,
+          'members': [
+            {'userId': isOwner ? 'me-uuid' : 'friend-uuid', 'nickname': '콩이아빠', 'photoFileId': 'face-1', 'isOwner': true},
+            {'userId': isOwner ? 'friend-uuid' : 'me-uuid', 'nickname': '콩이엄마', 'photoFileId': null, 'isOwner': false},
+          ],
+          'targets': [
+            {'id': 'p1', 'name': '콩이', 'photoFileId': 'pet-1', 'tint': '#FF8A5B', 'archived': false},
+            {'id': 'self', 'name': '콩이아빠', 'photoFileId': 'face-1', 'tint': null, 'archived': false},
+          ],
+        };
+
+    test('참여한 다이어리는 멤버의 나를 알아보고, 주인의 아이들을 서버가 준 이름·사진으로 담는다', () async {
+      api.on('GET', '/diaries', (r) => ok(page([sharedJson(isOwner: false)])));
+      api.on('GET', '/diary-posts', (r) => ok(page([
+            {
+              ..._postJson(authorId: 'friend-uuid'),
+              'author': {'userId': 'friend-uuid', 'nickname': '콩이아빠', 'photoFileId': 'face-1'},
+            },
+          ])));
+      api.on('GET', '/diary-comments', (r) => ok(page(const [])));
+
+      final book = await repo.fetch();
+
+      final diary = book.diaries.single;
+      expect(diary.shared, isTrue);
+      expect(diary.isOwner, isFalse);
+      expect(diary.inviteCode, isNull);
+      expect(diary.owner!.name, '콩이아빠');
+      expect(diary.members.last.isMe, isTrue);
+      expect(diary.targets.map((t) => t.name), ['콩이', '콩이아빠']);
+      expect(diary.targets.first.photoPath, 'server-file:pet-1');
+      expect(diary.targets.last.isSelf, isTrue);
+      // 주인의 아이들이라 내 추억 보관함과 상관없이 책장에 둔다
+      expect(diary.isArchivedWith({'p1'}), isFalse);
+      final post = book.posts.single;
+      expect(post.isMine, isFalse);
+      expect(post.author!.name, '콩이아빠');
+      expect(post.author!.photoPath, 'server-file:face-1');
+    });
+
+    test('내 다이어리는 아이 요약을 담지 않는다 — 내 반려동물 목록으로 그린다', () {
+      final diary = diaryFromApi(sharedJson(), myUserId: 'me-uuid');
+
+      expect(diary.isOwner, isTrue);
+      expect(diary.inviteCode, 'RUP-8F3K2Q');
+      expect(diary.targets, isEmpty);
+      expect(diary.memberCount, 2);
+      expect(diary.members.first.isMe, isTrue);
+    });
+
+    test('만들 때 공유 여부를 보낸다', () async {
+      api.on('POST', '/diaries', (r) {
+        expect(r.json!['shared'], isTrue);
+        return ok(sharedJson(), status: 201);
+      });
+
+      final created = await repo.createDiary(
+        name: '콩이의 하루',
+        targetIds: const ['p1'],
+        ribbon: kRibbonColors.first,
+        tint: kDiaryTints.first,
+        shared: true,
+      );
+
+      expect(created!.shared, isTrue);
+    });
+
+    test('개인 ↔ 공유 전환', () async {
+      api.on('PUT', '/diaries/:id/sharing', (r) {
+        expect(r.json, {'shared': false});
+        return ok(_diaryJson());
+      });
+
+      final diary = await repo.setShared('d1', false);
+
+      expect(diary.shared, isFalse);
+    });
+
+    test('초대 코드로 미리 보고, 참여하면 참여한 다이어리의 기록까지 다시 읽는다', () async {
+      api.on('GET', '/diary-invitations/:code', (r) => ok({
+            'diaryId': 'd1',
+            'name': '콩이의 하루',
+            'ownerNickname': '콩이아빠',
+            'memberCount': 2,
+            'maxMembers': 4,
+            'isMember': false,
+          }));
+      api.on('POST', '/diary-memberships', (r) {
+        expect(r.json, {'code': 'RUP-8F3K2Q'});
+        return ok(sharedJson(isOwner: false), status: 201);
+      });
+      api.on('GET', '/diaries', (r) => ok(page([sharedJson(isOwner: false)])));
+      api.on('GET', '/diary-posts', (r) => ok(page(const [])));
+      api.on('GET', '/diary-comments', (r) => ok(page(const [])));
+
+      final invitation = await repo.previewInvitation('RUP-8F3K2Q');
+      final book = await repo.join(invitation.code);
+
+      expect(invitation.name, '콩이의 하루');
+      expect(invitation.isFull, isFalse);
+      expect(api.sent('GET', '/diary-invitations/RUP-8F3K2Q'), hasLength(1));
+      expect(book.diaries.single.isOwner, isFalse);
+    });
+
+    test('나가기 · 멤버 내보내기', () async {
+      api.on('DELETE', '/diaries/:id/membership', (r) => noContent);
+      api.on('DELETE', '/diaries/:id/members/:userId', (r) => noContent);
+
+      await repo.leave('d1');
+      await repo.removeMember('d1', 'friend-uuid');
+
+      expect(api.sent('DELETE', '/diaries/d1/membership'), hasLength(1));
+      expect(api.sent('DELETE', '/diaries/d1/members/friend-uuid'), hasLength(1));
+    });
+  });
+
+  group('parseInviteCode', () {
+    test('QR 주소·코드·소문자·앞머리 없는 6자를 모두 초대 코드로 읽는다', () {
+      expect(parseInviteCode('rup://diary-invite/RUP-8F3K2Q'), 'RUP-8F3K2Q');
+      expect(parseInviteCode(' rup-8f3k2q '), 'RUP-8F3K2Q');
+      expect(parseInviteCode('8F3K2Q'), 'RUP-8F3K2Q');
+    });
+
+    test('초대 코드가 아니면 null', () {
+      expect(parseInviteCode('RUP-8F3K'), isNull);
+      expect(parseInviteCode('rup://pet-card/0428-117'), isNull);
+      expect(parseInviteCode('RUP-../../'), isNull);
+    });
+  });
+
   test('아이를 지울 때 다이어리 정리는 서버가 이미 했다', () async {
     await repo.dropTarget('p1');
 
diff --git a/flutter/test/receive_card_flow_test.dart b/flutter/test/receive_card_flow_test.dart
index 82de244..1b5c02e 100644
--- a/flutter/test/receive_card_flow_test.dart
+++ b/flutter/test/receive_card_flow_test.dart
@@ -5,8 +5,8 @@ import 'package:tma_app/features/pet_card/data/received_card_repository.dart';
 import 'package:tma_app/features/pet_card/domain/card_style.dart';
 import 'package:tma_app/features/pet_card/domain/card_view_mode.dart';
 import 'package:tma_app/features/pet_card/domain/received_card.dart';
-import 'package:tma_app/features/pet_card/presentation/pages/card_scanner_page.dart';
 import 'package:tma_app/shared/widgets/icons/rup_icon.dart';
+import 'package:tma_app/shared/widgets/qr_scanner_page.dart';
 
 import 'support/app_harness.dart';
 
diff --git a/flutter/test/shared_diary_flow_test.dart b/flutter/test/shared_diary_flow_test.dart
new file mode 100644
index 0000000..47ba6e9
--- /dev/null
+++ b/flutter/test/shared_diary_flow_test.dart
@@ -0,0 +1,397 @@
+import 'dart:convert';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:tma_app/core/api/api_exception.dart';
+import 'package:tma_app/features/diary/data/diary_repository.dart';
+import 'package:tma_app/features/diary/domain/diary.dart';
+import 'package:tma_app/features/diary/domain/diary_book.dart';
+import 'package:tma_app/features/diary/domain/diary_invitation.dart';
+import 'package:tma_app/features/diary/domain/mood.dart';
+import 'package:tma_app/features/diary/presentation/pages/diary_page.dart';
+import 'package:tma_app/features/diary/presentation/pages/diary_settings_page.dart';
+
+import 'support/app_harness.dart';
+
+const String _kCode = 'RUP-8F3K2Q';
+
+const DiaryMember _me = DiaryMember(id: kMeAuthorId, nickname: '나집사');
+const DiaryMember _dad = DiaryMember(id: 'dad', nickname: '콩이아빠', isOwner: true);
+const DiaryMember _mom = DiaryMember(id: 'mom', nickname: '콩이엄마');
+
+/// 내가 만든 공유 다이어리 — 나(주인) + 콩이엄마
+Diary _ownedShared() => Diary(
+      id: 'd1',
+      name: '콩이 성장일기',
+      targetIds: const ['pet-1'],
+      ribbon: kRibbonColors.first,
+      tint: kDiaryTints.first,
+      shared: true,
+      inviteCode: _kCode,
+      members: const [DiaryMember(id: kMeAuthorId, nickname: '나집사', isOwner: true), _mom],
+    );
+
+/// 초대받아 참여한 다이어리 — 콩이아빠(주인) + 나
+Diary _joined({String id = 'd2', String name = '함께 쓰는 다이어리'}) => Diary(
+      id: id,
+      name: name,
+      targetIds: const ['dad-pet'],
+      ribbon: kRibbonColors.first,
+      tint: kDiaryTints.first,
+      shared: true,
+      isOwner: false,
+      members: const [_dad, _me],
+      targets: const [DiaryTarget(id: 'dad-pet', name: '초코')],
+    );
+
+/// 서버 없이 공유 다이어리를 흉내 내는 저장소
+class _FakeSharedRepo implements DiaryRepository {
+  _FakeSharedRepo(this.book, {this.invitation});
+
+  DiaryBook book;
+  final DiaryInvitation? invitation;
+  final calls = <String>[];
+
+  @override
+  bool get canShare => true;
+
+  @override
+  Future<DiaryBook> fetch() async => book;
+
+  @override
+  Future<Diary?> createDiary({
+    required String name,
+    required List<String> targetIds,
+    required Color ribbon,
+    required Color tint,
+    String? coverPath,
+    bool shared = false,
+  }) async {
+    calls.add('create shared=$shared');
+    final diary = Diary(
+      id: 'new',
+      name: name,
+      targetIds: targetIds,
+      ribbon: ribbon,
+      tint: tint,
+      shared: shared,
+      inviteCode: shared ? _kCode : null,
+      members: shared ? const [DiaryMember(id: kMeAuthorId, isOwner: true)] : const [],
+    );
+    book = book.addDiary(diary);
+    return diary;
+  }
+
+  @override
+  Future<Diary> updateDiary(Diary diary) async => diary;
+
+  @override
+  Future<void> setMutedNotices(String diaryId, Set<DiaryNotice> muted) async => calls.add('muted $muted');
+
+  @override
+  Future<Diary> setShared(String diaryId, bool shared) async {
+    calls.add('shared $diaryId $shared');
+    final d = book.diary(diaryId)!;
+    final next = Diary(
+      id: d.id,
+      name: d.name,
+      targetIds: d.targetIds,
+      ribbon: d.ribbon,
+      tint: d.tint,
+      shared: shared,
+      inviteCode: shared ? _kCode : null,
+      members: shared ? d.members.where((m) => m.isOwner).toList() : const [],
+    );
+    book = book.updateDiary(next);
+    return next;
+  }
+
+  @override
+  Future<DiaryInvitation> previewInvitation(String code) async {
+    calls.add('preview $code');
+    final found = invitation;
+    if (found == null) throw ApiException.fromCode('DIARY_003');
+    return found;
+  }
+
+  @override
+  Future<DiaryBook> join(String code) async {
+    calls.add('join $code');
+    book = book.addDiary(_joined());
+    return book;
+  }
+
+  @override
+  Future<void> leave(String diaryId) async => calls.add('leave $diaryId');
+
+  @override
+  Future<void> removeMember(String diaryId, String memberId) async {
+    calls.add('remove $diaryId $memberId');
+    // 서버처럼 멤버를 빼고 초대 코드를 바꾼다
+    final d = book.diary(diaryId)!;
+    book = book.updateDiary(Diary(
+      id: d.id,
+      name: d.name,
+      targetIds: d.targetIds,
+      ribbon: d.ribbon,
+      tint: d.tint,
+      shared: d.shared,
+      inviteCode: 'RUP-NEW000',
+      members: d.members.where((m) => m.id != memberId).toList(),
+    ));
+  }
+
+  @override
+  Future<void> deleteDiary(String diaryId) async {}
+
+  @override
+  Future<DiaryPost> addPost({
+    required String diaryId,
+    required DateTime date,
+    required String text,
+    Mood? mood,
+    String? photoPath,
+  }) async =>
+      DiaryPost(id: 'p-new', diaryId: diaryId, date: date, createdAt: date, text: text);
+
+  @override
+  Future<DiaryPost> updatePostText(DiaryPost post, String text) async => post.copyWith(text: text);
+
+  @override
+  Future<void> deletePost(String postId) async {}
+
+  @override
+  Future<DiaryComment> addComment(String postId, String text) async =>
+      DiaryComment(id: 'c-new', postId: postId, text: text, createdAt: DateTime.now());
+
+  @override
+  Future<DiaryComment> updateComment(DiaryComment comment, String text) async => comment.copyWith(text: text);
+
+  @override
+  Future<void> deleteComment(String commentId) async {}
+
+  @override
+  Future<void> dropTarget(String targetId) async {}
+}
+
+Future<_FakeSharedRepo> _launch(WidgetTester tester, DiaryBook book, {DiaryInvitation? invitation}) async {
+  final repo = _FakeSharedRepo(book, invitation: invitation);
+  await launchSignedIn(
+    tester,
+    extra: {'pets.v1': jsonEncode([samplePet().toJson()])},
+    overrides: [diaryRepositoryProvider.overrideWithValue(repo)],
+  );
+  return repo;
+}
+
+Future<void> _openShelf(WidgetTester tester) async {
+  await tester.tap(find.bySemanticsLabel('일정·기록'));
+  await settle(tester);
+  await tester.tap(find.text('다이어리'));
+  await settle(tester);
+}
+
+Future<void> _openDiary(WidgetTester tester, String name) async {
+  await _openShelf(tester);
+  await tester.tap(find.text(name));
+  await settle(tester);
+  expect(find.byType(DiaryPage), findsOneWidget);
+}
+
+Future<void> _openSettings(WidgetTester tester, String name) async {
+  await _openDiary(tester, name);
+  await tester.tap(find.bySemanticsLabel('다이어리 설정'));
+  await settle(tester);
+  expect(find.byType(DiarySettingsPage), findsOneWidget);
+}
+
+Future<void> _tapVisible(WidgetTester tester, Finder finder) async {
+  await tester.ensureVisible(finder);
+  await tester.pump();
+  await tester.tap(finder);
+  await settle(tester);
+}
+
+void main() {
+  testWidgets('주인은 멤버와 초대 코드를 보고, 멤버를 내보낼 수 있다', (tester) async {
+    final repo = await _launch(tester, DiaryBook(diaries: [_ownedShared()]));
+    await _openDiary(tester, '콩이 성장일기');
+    expect(find.text('2/4'), findsOneWidget);
+
+    await tester.tap(find.bySemanticsLabel('다이어리 설정'));
+    await settle(tester);
+    expect(find.text('멤버'), findsOneWidget);
+    expect(find.text('2/4'), findsOneWidget);
+    expect(find.text('주인'), findsOneWidget);
+    expect(find.text('콩이엄마'), findsOneWidget);
+    expect(find.text('2명 더 초대할 수 있어요'), findsOneWidget);
+    await tester.ensureVisible(find.text(_kCode));
+    expect(find.text(_kCode), findsOneWidget);
+
+    await _tapVisible(tester, find.bySemanticsLabel('콩이엄마님 내보내기'));
+    expect(find.text('콩이엄마님을 내보낼까요?'), findsOneWidget);
+    await tester.tap(find.widgetWithText(GestureDetector, '내보내기').last);
+    await settle(tester);
+
+    expect(repo.calls, contains('remove d1 mom'));
+    expect(find.text('콩이엄마님을 내보냈어요'), findsOneWidget);
+    expect(find.text('1/4'), findsOneWidget);
+    // 내보내면 서버가 초대 코드를 바꾼다 — 다시 읽어 새 코드를 보여 준다
+    await tester.ensureVisible(find.text('RUP-NEW000'));
+    expect(find.text(_kCode), findsNothing);
+  });
+
+  testWidgets('멤버가 있는 다이어리를 개인으로 바꾸면 먼저 묻는다', (tester) async {
+    final repo = await _launch(tester, DiaryBook(diaries: [_ownedShared()]));
+    await _openSettings(tester, '콩이 성장일기');
+
+    await tester.tap(find.text('개인 다이어리'));
+    await settle(tester);
+    expect(find.text('개인 다이어리로 전환할까요?'), findsOneWidget);
+
+    await tester.tap(find.text('전환하기'));
+    await settle(tester);
+
+    expect(repo.calls, contains('shared d1 false'));
+    expect(find.text('개인 다이어리로 전환했어요'), findsOneWidget);
+    expect(find.text('멤버'), findsNothing);
+  });
+
+  testWidgets('참여한 다이어리는 만든 사람을 보여 주고, 나갈 수 있다', (tester) async {
+    final repo = await _launch(tester, DiaryBook(diaries: [_joined()]));
+    await _openSettings(tester, '함께 쓰는 다이어리');
+
+    expect(find.text('콩이아빠님이 만든 다이어리예요'), findsOneWidget);
+    expect(find.bySemanticsLabel('다이어리 수정하기'), findsNothing);
+    expect(find.text('내보내기'), findsNothing);
+    expect(find.text('다이어리 제거'), findsNothing);
+
+    await _tapVisible(tester, find.text('다이어리 나가기'));
+    expect(find.text('다이어리에서 나갈까요?'), findsOneWidget);
+    await tester.tap(find.text('나가기'));
+    await settle(tester);
+
+    expect(repo.calls, contains('leave d2'));
+    expect(find.text('다이어리에서 나왔어요'), findsOneWidget);
+    expect(find.byType(DiarySettingsPage), findsNothing);
+  });
+
+  testWidgets('초대 코드를 입력하고 확인하면 공유 다이어리에 참여한다', (tester) async {
+    final repo = await _launch(
+      tester,
+      DiaryBook.empty,
+      invitation: const DiaryInvitation(
+        code: _kCode,
+        diaryId: 'd2',
+        name: '함께 쓰는 다이어리',
+        ownerNickname: '콩이아빠',
+        memberCount: 1,
+        maxMembers: 4,
+        isMember: false,
+      ),
+    );
+    await _openShelf(tester);
+    await tester.tap(find.bySemanticsLabel('새 다이어리'));
+    await settle(tester);
+    await tester.tap(find.text('공유 다이어리 참여하기'));
+    await settle(tester);
+    expect(find.text('공유 다이어리 참여'), findsOneWidget);
+
+    await tester.enterText(find.byType(TextField), 'rup-8f3k2q');
+    await tester.pump();
+    await tester.tap(find.text('참여하기'));
+    await settle(tester);
+
+    expect(repo.calls, contains('preview $_kCode'));
+    expect(find.text('함께 쓰는 다이어리에\n참여하시겠어요?'), findsOneWidget);
+    await tester.tap(find.text('참여하기'));
+    await settle(tester);
+
+    expect(repo.calls, contains('join $_kCode'));
+    expect(find.text('공유 다이어리에 참여했어요'), findsOneWidget);
+    expect(find.text('함께 쓰는 다이어리'), findsOneWidget);
+  });
+
+  testWidgets('없는 초대 코드는 서버 안내로 멈추고 시트를 열어 둔다', (tester) async {
+    final repo = await _launch(tester, DiaryBook.empty);
+    await _openShelf(tester);
+    await tester.tap(find.bySemanticsLabel('새 다이어리'));
+    await settle(tester);
+    await tester.tap(find.text('공유 다이어리 참여하기'));
+    await settle(tester);
+
+    await tester.enterText(find.byType(TextField), 'RUP-ZZZZZZ');
+    await tester.pump();
+    await tester.tap(find.text('참여하기'));
+    await settle(tester);
+
+    expect(repo.calls, ['preview RUP-ZZZZZZ']);
+    expect(find.text('공유 다이어리 참여'), findsOneWidget);
+  });
+
+  testWidgets('공유 다이어리로 만들 수 있다', (tester) async {
+    final repo = await _launch(tester, DiaryBook.empty);
+    await _openShelf(tester);
+    await tester.tap(find.bySemanticsLabel('새 다이어리'));
+    await settle(tester);
+    await tester.tap(find.text('새 다이어리 만들기'));
+    await settle(tester);
+
+    await tester.tap(find.text('공유 다이어리'));
+    await tester.pump();
+    expect(find.text('만든 뒤 가족·지인을 초대해 함께 기록할 수 있어요.'), findsOneWidget);
+    await tester.enterText(find.byType(TextField).first, '가족 일기');
+    await _tapVisible(tester, find.text('다이어리 만들기'));
+
+    expect(repo.calls, contains('create shared=true'));
+    expect(find.text('공유 다이어리를 만들었어요'), findsOneWidget);
+  });
+
+  testWidgets('다른 멤버의 기록은 그 사람 이름으로 보이고, 고치거나 지울 수 없다', (tester) async {
+    final today = DateTime.now();
+    final post = DiaryPost(
+      id: 'p-dad',
+      diaryId: 'd2',
+      date: DateTime(today.year, today.month, today.day),
+      createdAt: today,
+      text: '초코랑 산책했어요',
+      authorId: 'dad',
+      author: _dad,
+    );
+    final comment = DiaryComment(id: 'c-dad', postId: 'p-dad', text: '귀엽다', createdAt: today, authorId: 'dad', author: _dad);
+    await _launch(tester, DiaryBook(diaries: [_joined()], posts: [post], comments: [comment]));
+    await _openDiary(tester, '함께 쓰는 다이어리');
+
+    expect(find.text('초코랑 산책했어요'), findsOneWidget);
+    expect(find.text('콩이아빠'), findsOneWidget);
+    expect(find.bySemanticsLabel('기록 관리'), findsNothing);
+
+    await _tapVisible(tester, find.textContaining('댓글'));
+    expect(find.text('귀엽다'), findsOneWidget);
+    expect(find.text('수정'), findsNothing);
+    expect(find.text('삭제'), findsNothing);
+  });
+
+  testWidgets('다른 멤버의 새 글은 알림에 나온다', (tester) async {
+    final now = DateTime.now();
+    final post = DiaryPost(
+      id: 'p-dad',
+      diaryId: 'd2',
+      date: DateTime(now.year, now.month, now.day),
+      createdAt: now.subtract(const Duration(minutes: 5)),
+      text: '초코랑 산책했어요',
+      authorId: 'dad',
+      author: _dad,
+    );
+    await _launch(tester, DiaryBook(diaries: [_joined()], posts: [post]));
+
+    // 새 글이 있으니 종에 점이 찍혀 있다
+    await tester.tap(find.bySemanticsLabel('알림, 새 알림 있음'));
+    await settle(tester);
+
+    expect(find.text('콩이아빠님이 새 글을 올렸어요'), findsOneWidget);
+    expect(find.text('“초코랑 산책했어요”'), findsOneWidget);
+    // 저녁 8시가 지났으면 기록 알림도 함께 나온다
+    expect(find.textContaining('함께 쓰는 다이어리 ·'), findsWidgets);
+  });
+}
diff --git a/flutter/test_live/api_contract_live_test.dart b/flutter/test_live/api_contract_live_test.dart
index 26f6a8f..94c01ca 100644
--- a/flutter/test_live/api_contract_live_test.dart
+++ b/flutter/test_live/api_contract_live_test.dart
@@ -26,6 +26,7 @@ import 'package:tma_app/features/auth/data/repositories/device_key_store.dart';
 import 'package:tma_app/features/auth/domain/social_provider.dart';
 import 'package:tma_app/features/diary/data/api_diary_repository.dart';
 import 'package:tma_app/features/diary/domain/diary.dart';
+import 'package:tma_app/features/diary/domain/diary_invitation.dart';
 import 'package:tma_app/features/diary/domain/mood.dart';
 import 'package:tma_app/features/mypage/data/profile_repository.dart';
 import 'package:tma_app/features/pet/data/repositories/api_pet_repository.dart';
@@ -192,7 +193,7 @@ void main() {
     final comment = await diaries.addComment(post.id, '귀여워');
     await diaries.updatePostText(post, '산책 다녀왔어요');
     await diaries.updateComment(comment, '정말 귀여워');
-    await diaries.updateDiary(diary.copyWith(mutedNotices: {DiaryNotice.reminder}));
+    await diaries.setMutedNotices(diary.id, {DiaryNotice.reminder});
 
     final diaryBook = await diaries.fetch();
     expect(diaryBook.wroteOn(diary.id, day), isTrue);
@@ -233,6 +234,104 @@ void main() {
     expect(reported, isEmpty, reason: '정상 흐름에서는 실패 알림이 없어야 한다');
   });
 
+  test('공유 다이어리 — 초대 코드로 함께 쓰고, 멤버의 글·사진이 서로 보이며, 내보내면 코드가 바뀐다', () async {
+    // 두 번째 회원 — 회원 id 는 prefs 한 자리에 남으므로 각자 붙잡아 둔다
+    final ownerId = prefs.getString(kAuthUserIdKey)!;
+    final memberSession = SessionStore(MemoryTokenVault());
+    final memberDio = DioClient(baseUrl: baseUrl, session: memberSession, onError: reported.add).dio;
+    final memberUploader = FileUploader(memberDio, reported.add);
+    final memberAuth = ApiAuthRepository(
+      dio: memberDio,
+      session: memberSession,
+      prefs: prefs,
+      deviceKeys: FixedDeviceKeyStore('live-member-${DateTime.now().microsecondsSinceEpoch}'),
+    );
+    await memberAuth.signIn(SocialProvider.kakao);
+    final memberId = prefs.getString(kAuthUserIdKey)!;
+    await prefs.setString(kAuthUserIdKey, ownerId);
+    addTearDown(() async {
+      if (memberSession.hasSession) await memberAuth.deleteAccount();
+      await prefs.setString(kAuthUserIdKey, ownerId);
+    });
+
+    final owner = ApiDiaryRepository(dio: dio, session: session, uploader: uploader, myUserId: () => ownerId);
+    final member = ApiDiaryRepository(
+      dio: memberDio,
+      session: memberSession,
+      uploader: memberUploader,
+      myUserId: () => memberId,
+    );
+    final today = DateTime.now();
+    final day = DateTime(today.year, today.month, today.day);
+
+    // 주인 — 공유 다이어리를 만들면 초대 코드가 생긴다
+    final shared = await owner.createDiary(
+      name: '함께 쓰는 하루',
+      targetIds: const ['self'],
+      ribbon: kRibbonColors[3],
+      tint: kDiaryTints[1],
+      coverPath: photoPath,
+      shared: true,
+    );
+    expect(shared!.shared, isTrue);
+    expect(shared.isOwner, isTrue);
+    final code = shared.inviteCode!;
+    expect(parseInviteCode(code), code);
+
+    // 멤버 — 미리 보고 참여한다
+    final invitation = await member.previewInvitation(code);
+    expect(invitation.name, '함께 쓰는 하루');
+    expect(invitation.isMember, isFalse);
+    var memberBook = await member.join(code);
+    final joined = memberBook.diaries.single;
+    expect(joined.isOwner, isFalse);
+    expect(joined.inviteCode, isNull);
+    expect(joined.owner!.name, '라이브 집사');
+    expect(joined.members.where((m) => m.isMe), hasLength(1));
+    expect(joined.targets.single.isSelf, isTrue);
+
+    // 멤버가 사진과 함께 기록하고, 주인이 댓글을 단다
+    final memberPost = await member.addPost(diaryId: joined.id, date: day, text: '같이 산책', photoPath: photoPath);
+    await owner.addComment(memberPost.id, '고마워요');
+
+    final ownerBook = await owner.fetch();
+    final seen = ownerBook.posts.firstWhere((p) => p.id == memberPost.id);
+    expect(seen.isMine, isFalse);
+    expect(seen.author!.id, memberId);
+    expect(ownerBook.diaries.firstWhere((d) => d.id == shared.id).memberCount, 2);
+
+    // 서로의 사진을 받을 수 있다 — 주인은 멤버의 기록 사진, 멤버는 주인의 표지
+    final postPhoto = await dio.get<List<int>>(
+      '$kFilesPath/${serverFileIdOf(seen.photoPath)}',
+      options: Options(responseType: ResponseType.bytes),
+    );
+    expect(postPhoto.data, _png);
+    final cover = await memberDio.get<List<int>>(
+      '$kFilesPath/${serverFileIdOf(joined.coverPath)}',
+      options: Options(responseType: ResponseType.bytes),
+    );
+    expect(cover.data, _png);
+
+    // 멤버에게는 주인의 댓글이 남의 댓글로 온다
+    memberBook = await member.fetch();
+    expect(memberBook.comments.single.isMine, isFalse);
+    expect(memberBook.comments.single.author!.name, '라이브 집사');
+
+    // 내보내면 멤버의 책장에서 사라지고, 예전 코드로는 다시 들어올 수 없다
+    await owner.removeMember(shared.id, memberId);
+    expect((await member.fetch()).diaries, isEmpty);
+    await expectLater(
+      member.previewInvitation(code),
+      throwsA(isA<DioException>().having((e) => (e.error! as ApiException).code, 'code', 'DIARY_003')),
+    );
+    final rotated = (await owner.fetch()).diaries.firstWhere((d) => d.id == shared.id);
+    expect(rotated.inviteCode, isNot(code));
+    expect(rotated.memberCount, 1);
+
+    reported.removeWhere((e) => e.code == 'DIARY_003');
+    expect(reported, isEmpty, reason: '정상 흐름에서는 실패 알림이 없어야 한다');
+  });
+
   test('규칙 위반은 사전 문구의 에러 코드로 돌아온다', () async {
     final diaries = ApiDiaryRepository(dio: dio, session: session, uploader: uploader, myUserId: () => null);
     final diary = (await diaries.fetch()).diaries.first;