diff --git a/backend/mpc-system/services/service-party-app/electron/main.ts b/backend/mpc-system/services/service-party-app/electron/main.ts
index 314bdb23..e848566d 100644
--- a/backend/mpc-system/services/service-party-app/electron/main.ts
+++ b/backend/mpc-system/services/service-party-app/electron/main.ts
@@ -2458,9 +2458,18 @@ app.whenReady().then(async () => {
   }
   createWindow();
 
-  app.on('activate', () => {
+  app.on('activate', async () => {
     if (BrowserWindow.getAllWindows().length === 0) {
       createWindow();
+      // macOS: 重新激活时检查并恢复 gRPC 连接
+      if (grpcClient && !grpcClient.isConnected()) {
+        debugLog.info('grpc', 'App activated, reconnecting to Message Router...');
+        try {
+          await connectAndRegisterToMessageRouter();
+        } catch (err) {
+          debugLog.error('grpc', `Failed to reconnect on activate: ${(err as Error).message}`);
+        }
+      }
     }
   });
 });
diff --git a/backend/mpc-system/services/service-party-app/electron/modules/tss-handler.ts b/backend/mpc-system/services/service-party-app/electron/modules/tss-handler.ts
index 4678a3b5..4686c30d 100644
--- a/backend/mpc-system/services/service-party-app/electron/modules/tss-handler.ts
+++ b/backend/mpc-system/services/service-party-app/electron/modules/tss-handler.ts
@@ -290,8 +290,11 @@ export class TSSHandler extends EventEmitter {
           this.isPrepared = false;
           this.messageBuffer = [];
           this.tssProcess = null;
-          // 清理消息监听器，防止下次 keygen 时重复注册
+          this.sessionId = null;
+          this.partyId = null;
+          // 清理消息监听器和 gRPC 流订阅，防止下次 keygen 时出错
           this.grpcClient.removeAllListeners('mpcMessage');
+          this.grpcClient.unsubscribeMessages();
 
           if (code === 0 && resultData) {
             try {
@@ -327,14 +330,19 @@ export class TSSHandler extends EventEmitter {
           this.isPrepared = false;
           this.messageBuffer = [];
           this.tssProcess = null;
-          // 清理消息监听器
+          this.sessionId = null;
+          this.partyId = null;
+          // 清理消息监听器和 gRPC 流订阅
           this.grpcClient.removeAllListeners('mpcMessage');
+          this.grpcClient.unsubscribeMessages();
           reject(err);
         });
 
       } catch (err) {
         this.isRunning = false;
         this.isPrepared = false;
+        this.sessionId = null;
+        this.partyId = null;
         reject(err);
       }
     });
@@ -674,8 +682,11 @@ export class TSSHandler extends EventEmitter {
           this.isPrepared = false;
           this.messageBuffer = [];
           this.tssProcess = null;
-          // 清理消息监听器
+          this.sessionId = null;
+          this.partyId = null;
+          // 清理消息监听器和 gRPC 流订阅
           this.grpcClient.removeAllListeners('mpcMessage');
+          this.grpcClient.unsubscribeMessages();
 
           if (code === 0 && resultData) {
             try {
@@ -709,14 +720,19 @@ export class TSSHandler extends EventEmitter {
           this.isPrepared = false;
           this.messageBuffer = [];
           this.tssProcess = null;
-          // 清理消息监听器
+          this.sessionId = null;
+          this.partyId = null;
+          // 清理消息监听器和 gRPC 流订阅
           this.grpcClient.removeAllListeners('mpcMessage');
+          this.grpcClient.unsubscribeMessages();
           reject(err);
         });
 
       } catch (err) {
         this.isRunning = false;
         this.isPrepared = false;
+        this.sessionId = null;
+        this.partyId = null;
         reject(err);
       }
     });
@@ -734,7 +750,11 @@ export class TSSHandler extends EventEmitter {
     this.isProcessReady = false;
     this.isPrepared = false;
     this.messageBuffer = [];
+    this.sessionId = null;
+    this.partyId = null;
+    // 清理消息监听器和 gRPC 流订阅
     this.grpcClient.removeAllListeners('mpcMessage');
+    this.grpcClient.unsubscribeMessages();
   }
 
   /**