diff --git a/CHANGELOG.md b/CHANGELOG.md
index 83920e6..57d5d0d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,6 +24,7 @@
 
 ### Added
 
+- Added safe signed Memos webhook rotation: create the replacement first, then remove the previous remote webhook before committing the new credentials.
 - Added configurable retention cleanup and a password-confirmed self-service account deletion flow.
 - Added append-only audit records for source management, invitations, posting, and administrator moderation.
 - Added verified SQLite/upload backups with retention, optional offsite copy, restore script, and installable daily WSL cron schedule.
diff --git a/app/api/sources/[id]/webhook/route.ts b/app/api/sources/[id]/webhook/route.ts
index 7236bfb..3a55121 100644
--- a/app/api/sources/[id]/webhook/route.ts
+++ b/app/api/sources/[id]/webhook/route.ts
@@ -1,15 +1,24 @@
 import { NextResponse } from "next/server";
 import { requireUser } from "@/lib/auth";
 import { db } from "@/lib/db";
+import { decrypt, encrypt } from "@/lib/crypto";
+import { createUserWebhook, deleteUserWebhook, getMemosIdentity } from "@/lib/memos";
 import { createWebhookSecret, webhookSecretHash } from "@/lib/webhook";
 import { requireSameOrigin } from "@/lib/security";
 
 export async function POST(request: Request, { params }: { params: Promise<{ id: string }> }) {
   try {
     requireSameOrigin(request); const user = await requireUser(); const { id: rawId } = await params; const id = Number(rawId);
-    const source = db.prepare("SELECT id,webhook_mode FROM sources WHERE id=? AND user_id=?").get(id, user.id) as { id: number; webhook_mode: string } | undefined;
+    const source = db.prepare("SELECT id,base_url,token_encrypted,remote_user,webhook_mode,webhook_remote_name FROM sources WHERE id=? AND user_id=?").get(id, user.id) as { id: number; base_url: string; token_encrypted: string; remote_user: string | null; webhook_mode: string; webhook_remote_name: string | null } | undefined;
     if (!source) return NextResponse.json({ error: "Not found" }, { status: 404 });
-    if (source.webhook_mode === "signed") return NextResponse.json({ error: "這個 Webhook 已由 Memos 自動管理；請重新連接來源以重新建立。" }, { status: 409 });
+    if (source.webhook_mode === "signed") {
+      const token = decrypt(source.token_encrypted); const identity = source.remote_user ? { name: source.remote_user } : await getMemosIdentity(source.base_url, token); const pathSecret = createWebhookSecret(); const signingSecret = createWebhookSecret(); const publicOrigin = (process.env.NEXT_PUBLIC_APP_URL || new URL(request.url).origin).replace(/\/$/, "");
+      const remote = await createUserWebhook(source.base_url, token, identity.name, { url: `${publicOrigin}/api/sync/webhook/${id}/${pathSecret}`, displayName: "Mebbling", signingSecret });
+      try { if (source.webhook_remote_name) await deleteUserWebhook(source.base_url, token, identity.name, source.webhook_remote_name); }
+      catch (error) { try { await deleteUserWebhook(source.base_url, token, identity.name, remote.name); } catch {} throw error; }
+      db.prepare("UPDATE sources SET webhook_secret_hash=?,webhook_remote_name=?,webhook_signing_secret_encrypted=? WHERE id=?").run(webhookSecretHash(pathSecret), remote.name, encrypt(signingSecret), id);
+      return NextResponse.json({ rotated: true });
+    }
     const secret = createWebhookSecret();
     db.prepare("UPDATE sources SET webhook_secret_hash=? WHERE id=?").run(webhookSecretHash(secret), id);
     const publicOrigin = (process.env.NEXT_PUBLIC_APP_URL || new URL(request.url).origin).replace(/\/$/, "");
diff --git a/app/dashboard/webhook-control.tsx b/app/dashboard/webhook-control.tsx
index 9c544a1..daa2237 100644
--- a/app/dashboard/webhook-control.tsx
+++ b/app/dashboard/webhook-control.tsx
@@ -3,17 +3,17 @@
 import { useState } from "react";
 
 export function WebhookControl({ sourceId, configured, automatic = false }: { sourceId: number; configured: boolean; automatic?: boolean }) {
-  const [url, setUrl] = useState(""); const [error, setError] = useState(""); const [busy, setBusy] = useState(false);
+  const [url, setUrl] = useState(""); const [error, setError] = useState(""); const [notice, setNotice] = useState(""); const [busy, setBusy] = useState(false);
   async function generate() {
-    setBusy(true); setError("");
+    setBusy(true); setError(""); setNotice("");
     try {
       const response = await fetch(`/api/sources/${sourceId}/webhook`, { method: "POST", headers: { Accept: "application/json" } });
-      const body = await response.json(); if (!response.ok) throw new Error(body.error || "無法產生 webhook URL"); setUrl(body.url);
+      const body = await response.json(); if (!response.ok) throw new Error(body.error || "無法產生 webhook URL"); if (body.rotated) setNotice("Webhook 已安全輪替。"); else setUrl(body.url);
     } catch (reason) { setError(reason instanceof Error ? reason.message : "無法產生 webhook URL"); }
     finally { setBusy(false); }
   }
   async function copy() { if (url) await navigator.clipboard.writeText(url); }
-  if (automatic) return <div className="webhook-control"><p className="meta">Webhook：已由 Memos 自動設定並驗證簽章。為避免讓遠端設定失效，此處不提供手動重產網址。</p></div>;
+  if (automatic) return <div className="webhook-control"><p className="meta">Webhook：已由 Memos 自動設定並驗證簽章。</p><button type="button" onClick={generate} disabled={busy}>{busy ? "輪替中…" : "安全輪替 Webhook"}</button>{notice && <p>{notice}</p>}{error && <p className="error">{error}</p>}</div>;
   return <div className="webhook-control"><p className="meta">Webhook：{configured ? "已設定" : "尚未設定"}</p>
     {url ? <><label className="sr-only" htmlFor={`webhook-${sourceId}`}>Webhook URL</label><input id={`webhook-${sourceId}`} readOnly value={url} onFocus={(event) => event.currentTarget.select()} /><div className="row"><button type="button" onClick={copy}>複製 URL</button><button type="button" className="danger" onClick={generate} disabled={busy}>重新產生</button></div><p className="meta">請立即複製到 Memos；重新整理後完整密鑰不會再顯示。</p></> : <button type="button" onClick={generate} disabled={busy}>{busy ? "產生中…" : configured ? "重新產生 webhook URL" : "產生 webhook URL"}</button>}
     {error && <p className="error">{error}</p>}
diff --git a/lib/memos.ts b/lib/memos.ts
index 343c32f..73f7230 100644
--- a/lib/memos.ts
+++ b/lib/memos.ts
@@ -10,6 +10,10 @@ export async function createUserWebhook(baseUrl: string, token: string, userName
   const user = userName.split("/").at(-1); if (!user) throw new Error("Invalid Memos user");
   return (await request(`${base(baseUrl)}/users/${encodeURIComponent(user)}/webhooks`, token, { method: "POST", body: JSON.stringify(webhook) })).json() as Promise<{ name: string }>;
 }
+export async function deleteUserWebhook(baseUrl: string, token: string, userName: string, webhookName: string) {
+  const user = userName.split("/").at(-1), webhook = webhookName.split("/").at(-1); if (!user || !webhook) throw new Error("Invalid Memos webhook");
+  await request(`${base(baseUrl)}/users/${encodeURIComponent(user)}/webhooks/${encodeURIComponent(webhook)}`, token, { method: "DELETE" });
+}
 export async function verifyMemos(baseUrl: string, token: string) { await request(`${base(baseUrl)}/memos?pageSize=1`, token); }
 export async function getMemosIdentity(baseUrl: string, token: string) {
   let user: MemosIdentity;