diff --git a/apps/mobile-shell/scripts/check-config.mjs b/apps/mobile-shell/scripts/check-config.mjs
index 56faf7445..06b6d1432 100644
--- a/apps/mobile-shell/scripts/check-config.mjs
+++ b/apps/mobile-shell/scripts/check-config.mjs
@@ -1318,6 +1318,7 @@ for (const snippet of [
   'normalizeHostBridgeShareOpenPayload(currentShareTarget)',
   'setMobileHostBridgeShareTarget',
   'request: HostBridgeRequest',
+  "throw invalidRequest('target is required')",
   'ok(request, true)',
   'resetMobileHostBridgeShareTargetForTest',
 ]) {
diff --git a/apps/mobile-shell/src/host-bridge/bridge.test.ts b/apps/mobile-shell/src/host-bridge/bridge.test.ts
index e16da2256..090dade71 100644
--- a/apps/mobile-shell/src/host-bridge/bridge.test.ts
+++ b/apps/mobile-shell/src/host-bridge/bridge.test.ts
@@ -922,6 +922,33 @@ describe('handleMobileHostBridgeMessage', () => {
     });
   });
 
+  test('share.setTarget 拒绝缺少目标且不清空已有目标', async () => {
+    expectOk(
+      await send(
+        request('share.setTarget', {
+          target: {
+            type: 'genarrative:share-target',
+            payload: {
+              title: '暖灯猫街',
+              work: 'PZ-00000001',
+            },
+          },
+        }),
+      ),
+    );
+
+    const invalid = await send(request('share.setTarget', {}));
+
+    expect(expectFailed(invalid).error.message).toBe('target is required');
+
+    expectOk(await send(request('share.open')));
+    expect(Share.share).toHaveBeenCalledWith({
+      title: '暖灯猫街',
+      message: 'https://app.genarrative.world/works/detail?work=PZ-00000001',
+      url: 'https://app.genarrative.world/works/detail?work=PZ-00000001',
+    });
+  });
+
   test('share.open 只把同源路径归一为公开主站分享 URL', async () => {
     const response = await send(
       request('share.open', {
diff --git a/apps/mobile-shell/src/host-bridge/share.ts b/apps/mobile-shell/src/host-bridge/share.ts
index ea7a9806b..40a917207 100644
--- a/apps/mobile-shell/src/host-bridge/share.ts
+++ b/apps/mobile-shell/src/host-bridge/share.ts
@@ -10,10 +10,15 @@ let currentShareTarget: unknown = null;
 
 export function setMobileHostBridgeShareTarget(request: HostBridgeRequest) {
   const payload = request.payload;
-  currentShareTarget =
+  const target =
     payload && typeof payload === 'object'
       ? (payload as { target?: unknown }).target
-      : null;
+      : undefined;
+  if (target === undefined) {
+    throw invalidRequest('target is required');
+  }
+
+  currentShareTarget = target;
   return ok(request, true);
 }