diff --git a/services/aams/include/accessible_ability_manager_service.h b/services/aams/include/accessible_ability_manager_service.h
index 276b27a44..a5d27c3fa 100644
--- a/services/aams/include/accessible_ability_manager_service.h
+++ b/services/aams/include/accessible_ability_manager_service.h
@@ -286,6 +286,7 @@ private:
     sptr<IRemoteObject::DeathRecipient> configCallbackDeathRecipient_ = nullptr;
     sptr<IRemoteObject::DeathRecipient> bundleManagerDeathRecipient_ = nullptr;
     std::vector<sptr<IAccessibleAbilityManagerStateObserver>> stateCallbacks_;
+    std::mutex mutex_;
 };
 } // namespace Accessibility
 } // namespace OHOS
diff --git a/services/aams/src/accessible_ability_manager_service.cpp b/services/aams/src/accessible_ability_manager_service.cpp
index b350982f7..d7ac7514c 100644
--- a/services/aams/src/accessible_ability_manager_service.cpp
+++ b/services/aams/src/accessible_ability_manager_service.cpp
@@ -291,10 +291,13 @@ uint32_t AccessibleAbilityManagerService::RegisterStateObserver(
             return;
         }
         callback->AsObject()->AddDeathRecipient(stateCallbackDeathRecipient_);
-        auto iter = std::find(stateCallbacks_.begin(), stateCallbacks_.end(), callback);
-        if (iter == stateCallbacks_.end()) {
-            stateCallbacks_.push_back(callback);
-            HILOG_INFO("RegisterStateObserver successfully");
+        {
+            std::lock_guard<std::mutex> lock(mutex_);
+            auto iter = std::find(stateCallbacks_.begin(), stateCallbacks_.end(), callback);
+            if (iter == stateCallbacks_.end()) {
+                stateCallbacks_.push_back(callback);
+                HILOG_INFO("RegisterStateObserver successfully");
+            }
         }
 
         sptr<AccessibilityAccountData> accountData = GetCurrentAccountData();