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 bfbd49de..1cef061a 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
@@ -384,13 +384,23 @@ export class TSSHandler extends EventEmitter {
    * 1. isPrepared=true, isRunning=false: 预订阅阶段，缓冲消息
    * 2. isPrepared=true, isRunning=true, isProcessReady=false: 进程启动中，缓冲消息
    * 3. isPrepared=true, isRunning=true, isProcessReady=true: 进程就绪，直接发送
+   *
+   * Note: gRPC message uses snake_case field names due to keepCase: true in proto-loader
    */
-  private handleIncomingMessage(message: {
-    messageId: string;
-    fromParty: string;
-    isBroadcast: boolean;
+  private handleIncomingMessage(rawMessage: {
+    message_id: string;
+    from_party: string;
+    is_broadcast: boolean;
     payload: Buffer;
   }): void {
+    // 转换为内部使用的 camelCase 格式
+    const message = {
+      messageId: rawMessage.message_id,
+      fromParty: rawMessage.from_party,
+      isBroadcast: rawMessage.is_broadcast,
+      payload: rawMessage.payload,
+    };
+
     // 消息去重检查
     if (this.database && message.messageId) {
       if (this.database.isMessageProcessed(message.messageId)) {