diff --git a/observer_agent/grpc_comm/server.cpp b/observer_agent/grpc_comm/server.cpp
index 9e0e76cdc09e983370d40e7e1c2d3bd53d0bcd60..ccfcb5c03123d4476a8a4f2ee21d0cecc4605f01 100644
--- a/observer_agent/grpc_comm/server.cpp
+++ b/observer_agent/grpc_comm/server.cpp
@@ -39,7 +39,7 @@ class PubSubServiceImpl final : public SubManager::Service
 
         for (auto iter = suber_topic_[cli_name].begin(); iter != suber_topic_[cli_name].end(); iter++)
         {
-            if (*iter == cli_topic)
+            if ((*iter & cli_topic) != 0)
             {
                 msg.set_text("this client name already subscribe the topic");
                 if (!writer->Write(msg))
@@ -51,9 +51,13 @@ class PubSubServiceImpl final : public SubManager::Service
             }
         }
 
+        sub_mutex.lock();
+
         suber_topic_[cli_name].push_back(cli_topic);
         suber_writer_[cli_name].push_back(writer);
 
+        sub_mutex.unlock();
+
         msg.set_text("topic: " + std::to_string(cli_topic) + " Subscribe success!");
         if (!writer->Write(msg))
         {
@@ -81,7 +85,7 @@ class PubSubServiceImpl final : public SubManager::Service
             i = 0;
             for (auto topic_item : iter->second)
             {
-                if (topic_item == cli_topic)
+                if ((topic_item & cli_topic) != 0)
                 {
                     auto &subscriber = suber_writer_[iter->first][i];
                     if (!subscriber->Write(msg))
@@ -103,6 +107,9 @@ class PubSubServiceImpl final : public SubManager::Service
         int cli_topic = request->topic();
         std::string cli_name = request->sub_name();
         int i = 0;
+        int unsub_flag = 0;
+
+        std::lock_guard<std::mutex> lock(sub_mutex);
 
         for (auto topic_item : suber_topic_[cli_name])
         {
@@ -110,10 +117,17 @@ class PubSubServiceImpl final : public SubManager::Service
             {
                 suber_topic_[cli_name].erase(suber_topic_[cli_name].begin() + i);
                 suber_writer_[cli_name].erase(suber_writer_[cli_name].begin() + i);
+                unsub_flag = 1;
                 break;
             }
             i++;
         }
+
+        if (!unsub_flag)
+        {
+            response->set_text("don't exist the topic: " + std::to_string(cli_topic));
+            return grpc::Status(grpc::StatusCode::INTERNAL, "Failed to UnSubscribe topic!");
+        }
         response->set_text("topic: " + std::to_string(cli_topic) + " UnSubscribe success!");
         return grpc::Status::OK;
     }
@@ -121,6 +135,7 @@ class PubSubServiceImpl final : public SubManager::Service
   private:
     std::unordered_map<std::string, std::vector<int>> suber_topic_;
     std::unordered_map<std::string, std::vector<ServerWriter<Message> *>> suber_writer_;
+    std::mutex sub_mutex;
 };
 
 std::unique_ptr<Server> server;