diff --git a/prisma/schema.prisma b/prisma/schema.prisma
index b9db9e3..c4352bf 100644
--- a/prisma/schema.prisma
+++ b/prisma/schema.prisma
@@ -166,6 +166,13 @@ model KnowledgeBase {
   title         String    @db.VarChar(255)
   description   String?   @db.Text
   coverKey      String?   @db.VarChar(100)
+  coverType     String    @default("custom") @db.VarChar(32)
+  coverIcon     String?   @db.VarChar(50)
+  coverColor    String?   @db.VarChar(20)
+  visibility    String    @default("private") @db.VarChar(16)
+  isPinned      Boolean   @default(false)
+  ownerType     String    @default("user") @db.VarChar(16)
+  isVerified    Boolean   @default(false)
   status        String    @default("active") @db.VarChar(32)
   itemCount     Int       @default(0)
   lastStudiedAt DateTime?
@@ -173,16 +180,33 @@ model KnowledgeBase {
   updatedAt     DateTime  @updatedAt
   deletedAt     DateTime?
 
-  user       User              @relation(fields: [userId], references: [id])
-  items      KnowledgeItem[]
-  sources    KnowledgeSource[]
-  candidates ImportCandidate[]
-  chunks     KnowledgeChunk[]
-  focusItems FocusItem[]
-  folders    KnowledgeFolder[]
+  user          User                      @relation(fields: [userId], references: [id])
+  items         KnowledgeItem[]
+  sources       KnowledgeSource[]
+  candidates    ImportCandidate[]
+  chunks        KnowledgeChunk[]
+  focusItems    FocusItem[]
+  folders       KnowledgeFolder[]
+  subscriptions KnowledgeBaseSubscription[]
 
   @@index([userId])
   @@index([status])
+  @@index([visibility])
+  @@index([ownerType])
+}
+
+model KnowledgeBaseSubscription {
+  id              String   @id @default(cuid())
+  userId          String
+  knowledgeBaseId String
+  createdAt       DateTime @default(now())
+
+  user          User          @relation(fields: [userId], references: [id])
+  knowledgeBase KnowledgeBase @relation(fields: [knowledgeBaseId], references: [id])
+
+  @@unique([userId, knowledgeBaseId])
+  @@index([userId])
+  @@index([knowledgeBaseId])
 }
 
 model Artifact {
diff --git a/src/modules/knowledge-base/knowledge-base.controller.ts b/src/modules/knowledge-base/knowledge-base.controller.ts
index 112cf79..de26358 100644
--- a/src/modules/knowledge-base/knowledge-base.controller.ts
+++ b/src/modules/knowledge-base/knowledge-base.controller.ts
@@ -65,4 +65,56 @@ export class KnowledgeBaseController {
   async deleteFolder(@Param('folderId') folderId: string) {
     return this.service.deleteFolder(folderId);
   }
+
+  // ── Pin ──
+
+  @Post(':id/pin')
+  @ApiOperation({ summary: '切换置顶状态' })
+  async togglePin(@CurrentUser() user: UserPayload, @Param('id') id: string) {
+    return this.service.togglePin(String(user?.id || 'anonymous'), id);
+  }
+
+  // ── Visibility ──
+
+  @Patch(':id/visibility')
+  @ApiOperation({ summary: '切换公开/私有' })
+  async setVisibility(
+    @CurrentUser() user: UserPayload,
+    @Param('id') id: string,
+    @Body() dto: { visibility: string },
+  ) {
+    return this.service.setVisibility(String(user?.id || 'anonymous'), id, dto.visibility);
+  }
+
+  // ── Subscribe ──
+
+  @Post(':id/subscribe')
+  @ApiOperation({ summary: '订阅知识库' })
+  async subscribe(@CurrentUser() user: UserPayload, @Param('id') id: string) {
+    return this.service.subscribe(String(user?.id || 'anonymous'), id);
+  }
+
+  @Delete(':id/subscribe')
+  @ApiOperation({ summary: '取消订阅' })
+  async unsubscribe(@CurrentUser() user: UserPayload, @Param('id') id: string) {
+    return this.service.unsubscribe(String(user?.id || 'anonymous'), id);
+  }
+
+  @Get('subscribed')
+  @ApiOperation({ summary: '已订阅知识库列表' })
+  async listSubscribed(@CurrentUser() user: UserPayload, @Query() pagination: PaginationDto) {
+    return this.service.listSubscribed(String(user?.id || 'anonymous'), pagination);
+  }
+
+  // ── Discover ──
+
+  @Get('discover')
+  @ApiOperation({ summary: '发现公开知识库' })
+  async discover(@Query('search') search?: string, @Query('page') page?: string, @Query('limit') limit?: string) {
+    return this.service.discoverPublic({
+      page: Number(page) || 1,
+      limit: Math.min(Number(limit) || 20, 100),
+      search,
+    });
+  }
 }
diff --git a/src/modules/knowledge-base/knowledge-base.repository.ts b/src/modules/knowledge-base/knowledge-base.repository.ts
index 76fdd04..199944c 100644
--- a/src/modules/knowledge-base/knowledge-base.repository.ts
+++ b/src/modules/knowledge-base/knowledge-base.repository.ts
@@ -5,13 +5,25 @@ import { PrismaService } from '../../infrastructure/database/prisma.service';
 export class KnowledgeBaseRepository {
   constructor(private readonly prisma: PrismaService) {}
 
-  async create(userId: string, dto: { title: string; description?: string; coverKey?: string }) {
+  async create(userId: string, dto: {
+    title: string;
+    description?: string;
+    coverKey?: string;
+    coverType?: string;
+    coverIcon?: string;
+    coverColor?: string;
+    visibility?: string;
+  }) {
     return this.prisma.knowledgeBase.create({
       data: {
         userId,
         title: dto.title,
         description: dto.description ?? '',
         coverKey: dto.coverKey ?? null,
+        coverType: dto.coverType ?? 'custom',
+        coverIcon: dto.coverIcon ?? null,
+        coverColor: dto.coverColor ?? null,
+        visibility: dto.visibility ?? 'private',
         status: 'active',
         itemCount: 0,
       },
@@ -22,12 +34,41 @@ export class KnowledgeBaseRepository {
     return this.prisma.knowledgeBase.findUnique({ where: { id } });
   }
 
-  async findAllByUserId(userId: string, pagination?: { page?: number; limit?: number }) {
-    const page = pagination?.page ?? 1;
-    const limit = pagination?.limit ?? 20;
+  async findAllByUserId(
+    userId: string,
+    opts?: {
+      page?: number;
+      limit?: number;
+      visibility?: string;
+      ownerType?: string;
+    },
+  ) {
+    const page = opts?.page ?? 1;
+    const limit = opts?.limit ?? 20;
+    const where: any = { userId, deletedAt: null };
+    if (opts?.visibility) where.visibility = opts.visibility;
+    if (opts?.ownerType) where.ownerType = opts.ownerType;
     return this.prisma.knowledgeBase.findMany({
-      where: { userId, deletedAt: null },
-      orderBy: { updatedAt: 'desc' },
+      where,
+      orderBy: [{ isPinned: 'desc' }, { updatedAt: 'desc' }],
+      skip: (page - 1) * limit,
+      take: limit,
+    });
+  }
+
+  async findAllPublic(opts?: { page?: number; limit?: number; search?: string }) {
+    const page = opts?.page ?? 1;
+    const limit = opts?.limit ?? 20;
+    const where: any = { visibility: 'public', deletedAt: null };
+    if (opts?.search) {
+      where.OR = [
+        { title: { contains: opts.search } },
+        { description: { contains: opts.search } },
+      ];
+    }
+    return this.prisma.knowledgeBase.findMany({
+      where,
+      orderBy: [{ isPinned: 'desc' }, { updatedAt: 'desc' }],
       skip: (page - 1) * limit,
       take: limit,
     });
@@ -39,13 +80,36 @@ export class KnowledgeBaseRepository {
     });
   }
 
-  async update(id: string, dto: { title?: string; description?: string }) {
+  async update(id: string, dto: {
+    title?: string;
+    description?: string;
+    coverKey?: string;
+    coverType?: string;
+    coverIcon?: string;
+    coverColor?: string;
+    visibility?: string;
+    isPinned?: boolean;
+  }) {
     return this.prisma.knowledgeBase.update({
       where: { id },
       data: dto,
     });
   }
 
+  async togglePin(id: string, isPinned: boolean) {
+    return this.prisma.knowledgeBase.update({
+      where: { id },
+      data: { isPinned },
+    });
+  }
+
+  async setVisibility(id: string, visibility: string) {
+    return this.prisma.knowledgeBase.update({
+      where: { id },
+      data: { visibility },
+    });
+  }
+
   async softDelete(id: string) {
     await this.prisma.knowledgeBase.update({
       where: { id },
@@ -53,4 +117,40 @@ export class KnowledgeBaseRepository {
     });
     return true;
   }
+
+  // ── Subscription ──
+
+  async subscribe(userId: string, knowledgeBaseId: string) {
+    return this.prisma.knowledgeBaseSubscription.create({
+      data: { userId, knowledgeBaseId },
+    });
+  }
+
+  async unsubscribe(userId: string, knowledgeBaseId: string) {
+    await this.prisma.knowledgeBaseSubscription.deleteMany({
+      where: { userId, knowledgeBaseId },
+    });
+    return true;
+  }
+
+  async findSubscribed(userId: string, opts?: { page?: number; limit?: number }) {
+    const page = opts?.page ?? 1;
+    const limit = opts?.limit ?? 20;
+    return this.prisma.knowledgeBase.findMany({
+      where: {
+        subscriptions: { some: { userId } },
+        deletedAt: null,
+      },
+      orderBy: { updatedAt: 'desc' },
+      skip: (page - 1) * limit,
+      take: limit,
+    });
+  }
+
+  async isSubscribed(userId: string, knowledgeBaseId: string): Promise<boolean> {
+    const sub = await this.prisma.knowledgeBaseSubscription.findUnique({
+      where: { userId_knowledgeBaseId: { userId, knowledgeBaseId } },
+    });
+    return !!sub;
+  }
 }
diff --git a/src/modules/knowledge-base/knowledge-base.service.ts b/src/modules/knowledge-base/knowledge-base.service.ts
index ad65878..eac095c 100644
--- a/src/modules/knowledge-base/knowledge-base.service.ts
+++ b/src/modules/knowledge-base/knowledge-base.service.ts
@@ -26,8 +26,8 @@ export class KnowledgeBaseService {
     return this.enrichWithCoverUrl(await this.repository.create(userId, dto));
   }
 
-  async findAll(userId: string, pagination: { page?: number; limit?: number }) {
-    const kbs = await this.repository.findAllByUserId(userId, pagination);
+  async findAll(userId: string, opts?: { page?: number; limit?: number; visibility?: string; ownerType?: string }) {
+    const kbs = await this.repository.findAllByUserId(userId, opts);
     return Promise.all(kbs.map(kb => this.enrichWithCoverUrl(kb)));
   }
 
@@ -46,9 +46,11 @@ export class KnowledgeBaseService {
 
   async findOne(userId: string, id: string) {
     const kb = await this.repository.findById(id);
-    if (!kb || String(kb.userId) !== userId) {
-      throw new NotFoundException('知识库不存在');
-    }
+    if (!kb || kb.deletedAt) throw new NotFoundException('知识库不存在');
+    // 公开库允许任何人查看
+    if (kb.visibility === 'public') return kb;
+    // 私有库只能 owner 查看
+    if (String(kb.userId) !== userId) throw new NotFoundException('知识库不存在');
     return kb;
   }
 
@@ -72,6 +74,49 @@ export class KnowledgeBaseService {
     return this.repository.softDelete(id);
   }
 
+  // ── Pin ──
+
+  async togglePin(userId: string, id: string) {
+    const kb = await this.repository.findById(id);
+    if (!kb || String(kb.userId) !== userId) throw new NotFoundException('知识库不存在');
+    return this.repository.togglePin(id, !kb.isPinned);
+  }
+
+  // ── Visibility ──
+
+  async setVisibility(userId: string, id: string, visibility: string) {
+    const kb = await this.repository.findById(id);
+    if (!kb || String(kb.userId) !== userId) throw new NotFoundException('知识库不存在');
+    if (!['private', 'public'].includes(visibility)) throw new BadRequestException('visibility 必须为 private 或 public');
+    return this.repository.setVisibility(id, visibility);
+  }
+
+  // ── Subscribe ──
+
+  async subscribe(userId: string, knowledgeBaseId: string) {
+    const kb = await this.repository.findById(knowledgeBaseId);
+    if (!kb || kb.deletedAt) throw new NotFoundException('知识库不存在');
+    if (kb.visibility !== 'public') throw new BadRequestException('只能订阅公开知识库');
+    if (kb.userId === userId) throw new BadRequestException('不能订阅自己的知识库');
+    return this.repository.subscribe(userId, knowledgeBaseId);
+  }
+
+  async unsubscribe(userId: string, knowledgeBaseId: string) {
+    return this.repository.unsubscribe(userId, knowledgeBaseId);
+  }
+
+  async listSubscribed(userId: string, opts?: { page?: number; limit?: number }) {
+    const kbs = await this.repository.findSubscribed(userId, opts);
+    return Promise.all(kbs.map(kb => this.enrichWithCoverUrl(kb)));
+  }
+
+  // ── Discover ──
+
+  async discoverPublic(opts?: { page?: number; limit?: number; search?: string }) {
+    const kbs = await this.repository.findAllPublic(opts);
+    return Promise.all(kbs.map(kb => this.enrichWithCoverUrl(kb)));
+  }
+
   // ── Folder CRUD ──
 
   async createFolder(kbId: string, dto: { name: string; parentId?: string }) {