diff --git a/apps/api/src/index.ts b/apps/api/src/index.ts
index 9416ff31..7cbef659 100644
--- a/apps/api/src/index.ts
+++ b/apps/api/src/index.ts
@@ -3852,7 +3852,10 @@ const ensureUserWorkspace = async (db: D1Database, userId: string, username: str
   const existing = await db.prepare(
     `SELECT workspace_id, role FROM workspace_members WHERE user_id = ? LIMIT 1`
   ).bind(userId).first<{ workspace_id: string; role: "owner" | "member" }>();
-  if (existing) return { workspaceId: existing.workspace_id, role: existing.role };
+  if (existing) {
+    await ensureWorkspaceTemplateSeed(db, existing.workspace_id);
+    return { workspaceId: existing.workspace_id, role: existing.role };
+  }
 
   const defaultOwner = await db.prepare(
     `SELECT user_id FROM workspace_members WHERE workspace_id = ? LIMIT 1`
@@ -3864,7 +3867,10 @@ const ensureUserWorkspace = async (db: D1Database, userId: string, username: str
     const claimed = await db.prepare(
       `SELECT workspace_id, role FROM workspace_members WHERE user_id = ? LIMIT 1`
     ).bind(userId).first<{ workspace_id: string; role: "owner" | "member" }>();
-    if (claimed) return { workspaceId: claimed.workspace_id, role: claimed.role };
+    if (claimed) {
+      await ensureWorkspaceTemplateSeed(db, claimed.workspace_id);
+      return { workspaceId: claimed.workspace_id, role: claimed.role };
+    }
   }
 
   const workspaceId = createId("ws");
@@ -3880,6 +3886,7 @@ const ensureUserWorkspace = async (db: D1Database, userId: string, username: str
        VALUES (?, ?, NULL, ?, ?, 'notebook', ?, ?, ?, ?)`
     ).bind(notebook.id, workspaceId, notebook.name, notebook.slug, notebook.color, notebook.sortOrder, now, now)),
   ]);
+  await ensureWorkspaceTemplateSeed(db, workspaceId);
   return { workspaceId, role: "member" as const };
 };
 
@@ -3891,6 +3898,30 @@ const createDefaultNotebookRows = (workspaceId: string, _now: string) => [
   { id: `${workspaceId}_personal`, name: "生活个人", slug: "personal-life", color: "#ea580c", sortOrder: 50 },
 ];
 
+const ensureWorkspaceTemplateSeed = async (db: D1Database, workspaceId: string) => {
+  const now = isoNow();
+  const templateId = `${workspaceId}_template_project_weekly`;
+  const contentMarkdown = "## 本周进展\n\n- \n\n## 关键成果\n\n- \n\n## 风险与阻塞\n\n- \n\n## 下周计划\n\n- [ ] \n\n## 需要协助\n\n- ";
+  const contentJson = markdownToDoc(contentMarkdown);
+
+  await db.prepare(
+    `INSERT OR IGNORE INTO memo_templates (
+       id, workspace_id, name, description, title, content_json, content_markdown, tags_json, created_at, updated_at
+     ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`
+  ).bind(
+    templateId,
+    workspaceId,
+    "项目周报模板",
+    "每周同步项目进展、风险与下一步计划",
+    "项目周报｜第 {{周次}} 周",
+    JSON.stringify(contentJson),
+    contentMarkdown,
+    JSON.stringify(["项目管理", "周报"]),
+    now,
+    now,
+  ).run();
+};
+
 const createSession = async (c: AppContext, user: UserRow, requestedDeviceId?: string) => {
   const token = randomToken(SESSION_TOKEN_BYTES);
   const id = createId("sess");
diff --git a/migrations/0017_seed_default_templates.sql b/migrations/0017_seed_default_templates.sql
new file mode 100644
index 00000000..53244e26
--- /dev/null
+++ b/migrations/0017_seed_default_templates.sql
@@ -0,0 +1,31 @@
+PRAGMA foreign_keys = ON;
+
+-- Replace the original oversized demo template with a compact, reusable example.
+DELETE FROM memo_templates
+WHERE name = '产品周报模板'
+  AND description = '用于每周产品进展记录';
+
+DELETE FROM memo_templates
+WHERE name = '项目周报模板'
+  AND description = '每周同步项目进展、风险与下一步计划';
+
+INSERT OR IGNORE INTO memo_templates (
+  id,
+  workspace_id,
+  name,
+  description,
+  title,
+  content_json,
+  content_markdown,
+  tags_json
+)
+SELECT
+  id || '_template_project_weekly',
+  id,
+  '项目周报模板',
+  '每周同步项目进展、风险与下一步计划',
+  '项目周报｜第 {{周次}} 周',
+  '{"type":"doc","content":[{"type":"heading","attrs":{"level":2},"content":[{"type":"text","text":"本周进展"}]},{"type":"paragraph"},{"type":"heading","attrs":{"level":2},"content":[{"type":"text","text":"关键成果"}]},{"type":"paragraph"},{"type":"heading","attrs":{"level":2},"content":[{"type":"text","text":"风险与阻塞"}]},{"type":"paragraph"},{"type":"heading","attrs":{"level":2},"content":[{"type":"text","text":"下周计划"}]},{"type":"bulletList","content":[{"type":"listItem","content":[{"type":"paragraph"}]}]},{"type":"heading","attrs":{"level":2},"content":[{"type":"text","text":"需要协助"}]},{"type":"paragraph"}]}',
+  '## 本周进展\n\n- \n\n## 关键成果\n\n- \n\n## 风险与阻塞\n\n- \n\n## 下周计划\n\n- [ ] \n\n## 需要协助\n\n- ',
+  '["项目管理","周报"]'
+FROM workspaces;