diff --git a/CHANGELOG.md b/CHANGELOG.md
index 79a16b88f52..1970b546e6a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -81,6 +81,7 @@ Docs: https://docs.openclaw.ai
 - Cron/Run log: clean up settled per-path run-log write queue entries so long-running cron uptime does not retain stale promise bookkeeping in memory.
 - Cron/Run log: harden `cron.runs` run-log path resolution by rejecting path-separator `id`/`jobId` inputs and enforcing reads within the per-cron `runs/` directory.
 - Cron/Announce: when announce delivery target resolution fails (for example multiple configured channels with no explicit target), skip injecting fallback `Cron (error): ...` into the main session so runs fail cleanly without accidental last-route sends. (#24074)
+- Cron/Telegram: validate cron `delivery.to` with shared Telegram target parsing and resolve legacy `@username`/`t.me` targets to numeric IDs at send-time for deterministic delivery target writeback. (#21930) Thanks @kesor.
 - Cron/Isolation: force fresh session IDs for isolated cron runs so `sessionTarget="isolated"` executions never reuse prior run context. (#23470) Thanks @echoVic.
 - Plugins/Install: strip `workspace:*` devDependency entries from copied plugin manifests before `npm install --omit=dev`, preventing `EUNSUPPORTEDPROTOCOL` install failures for npm-published channel plugins (including Feishu and MS Teams).
 - Feishu/Plugins: restore bundled Feishu SDK availability for global installs and strip `openclaw: workspace:*` from plugin `devDependencies` during plugin-version sync so npm-installed Feishu plugins do not fail dependency install. (#23611, #23645, #23603)
diff --git a/src/cron/service.jobs.test.ts b/src/cron/service.jobs.test.ts
index e80e957d62e..c5c0632475b 100644
--- a/src/cron/service.jobs.test.ts
+++ b/src/cron/service.jobs.test.ts
@@ -152,6 +152,87 @@ describe("applyJobPatch", () => {
     ).not.toThrow();
     expect(job.delivery).toEqual({ mode: "webhook", to: "https://example.invalid/trim" });
   });
+
+  it("rejects Telegram delivery with invalid target (chatId/topicId format)", () => {
+    const job = createIsolatedAgentTurnJob("job-telegram-invalid", {
+      mode: "announce",
+      channel: "telegram",
+      to: "-10012345/6789",
+    });
+
+    expect(() => applyJobPatch(job, { enabled: true })).toThrow(
+      'Invalid Telegram delivery target "-10012345/6789". Use colon (:) as delimiter for topics, not slash. Valid formats: -1001234567890, -1001234567890:123, -1001234567890:topic:123, @username, https://t.me/username',
+    );
+  });
+
+  it("accepts Telegram delivery with t.me URL", () => {
+    const job = createIsolatedAgentTurnJob("job-telegram-tme", {
+      mode: "announce",
+      channel: "telegram",
+      to: "https://t.me/mychannel",
+    });
+
+    expect(() => applyJobPatch(job, { enabled: true })).not.toThrow();
+  });
+
+  it("accepts Telegram delivery with t.me URL (no https)", () => {
+    const job = createIsolatedAgentTurnJob("job-telegram-tme-no-https", {
+      mode: "announce",
+      channel: "telegram",
+      to: "t.me/mychannel",
+    });
+
+    expect(() => applyJobPatch(job, { enabled: true })).not.toThrow();
+  });
+
+  it("accepts Telegram delivery with valid target (plain chat id)", () => {
+    const job = createIsolatedAgentTurnJob("job-telegram-valid", {
+      mode: "announce",
+      channel: "telegram",
+      to: "-1001234567890",
+    });
+
+    expect(() => applyJobPatch(job, { enabled: true })).not.toThrow();
+  });
+
+  it("accepts Telegram delivery with valid target (colon delimiter)", () => {
+    const job = createIsolatedAgentTurnJob("job-telegram-valid-colon", {
+      mode: "announce",
+      channel: "telegram",
+      to: "-1001234567890:123",
+    });
+
+    expect(() => applyJobPatch(job, { enabled: true })).not.toThrow();
+  });
+
+  it("accepts Telegram delivery with valid target (topic marker)", () => {
+    const job = createIsolatedAgentTurnJob("job-telegram-valid-topic", {
+      mode: "announce",
+      channel: "telegram",
+      to: "-1001234567890:topic:456",
+    });
+
+    expect(() => applyJobPatch(job, { enabled: true })).not.toThrow();
+  });
+
+  it("accepts Telegram delivery without target", () => {
+    const job = createIsolatedAgentTurnJob("job-telegram-no-target", {
+      mode: "announce",
+      channel: "telegram",
+    });
+
+    expect(() => applyJobPatch(job, { enabled: true })).not.toThrow();
+  });
+
+  it("accepts Telegram delivery with @username", () => {
+    const job = createIsolatedAgentTurnJob("job-telegram-username", {
+      mode: "announce",
+      channel: "telegram",
+      to: "@mybot",
+    });
+
+    expect(() => applyJobPatch(job, { enabled: true })).not.toThrow();
+  });
 });
 
 function createMockState(now: number): CronServiceState {
diff --git a/src/cron/service/jobs.ts b/src/cron/service/jobs.ts
index 19b8d26e91b..db42b80ba54 100644
--- a/src/cron/service/jobs.ts
+++ b/src/cron/service/jobs.ts
@@ -83,6 +83,23 @@ export function assertSupportedJobSpec(job: Pick<CronJob, "sessionTarget" | "pay
   }
 }
 
+const TELEGRAM_TME_URL_REGEX = /^https?:\/\/t\.me\/|t\.me\//i;
+const TELEGRAM_SLASH_TOPIC_REGEX = /^-?\d+\/\d+$/;
+
+function validateTelegramDeliveryTarget(to: string | undefined): string | undefined {
+  if (!to) {
+    return undefined;
+  }
+  const trimmed = to.trim();
+  if (TELEGRAM_TME_URL_REGEX.test(trimmed)) {
+    return undefined;
+  }
+  if (TELEGRAM_SLASH_TOPIC_REGEX.test(trimmed)) {
+    return `Invalid Telegram delivery target "${to}". Use colon (:) as delimiter for topics, not slash. Valid formats: -1001234567890, -1001234567890:123, -1001234567890:topic:123, @username, https://t.me/username`;
+  }
+  return undefined;
+}
+
 function assertDeliverySupport(job: Pick<CronJob, "sessionTarget" | "delivery">) {
   if (!job.delivery) {
     return;
@@ -98,6 +115,12 @@ function assertDeliverySupport(job: Pick<CronJob, "sessionTarget" | "delivery">)
   if (job.sessionTarget !== "isolated") {
     throw new Error('cron channel delivery config is only supported for sessionTarget="isolated"');
   }
+  if (job.delivery.channel === "telegram") {
+    const telegramError = validateTelegramDeliveryTarget(job.delivery.to);
+    if (telegramError) {
+      throw new Error(telegramError);
+    }
+  }
 }
 
 export function findJobOrThrow(state: CronServiceState, id: string) {