diff --git a/automotive/vehicle/2.0/default/common/src/VehiclePropertyStore.cpp b/automotive/vehicle/2.0/default/common/src/VehiclePropertyStore.cpp
index 24b777c..6087bfa 100644
--- a/automotive/vehicle/2.0/default/common/src/VehiclePropertyStore.cpp
+++ b/automotive/vehicle/2.0/default/common/src/VehiclePropertyStore.cpp
@@ -58,6 +58,8 @@
         return false;
     }
     // update the propertyValue.
+    // The timestamp in propertyStore should only be updated by the server side. It indicates
+    // the time when the event is generated by the server.
     valueToUpdate->timestamp = propValue.timestamp;
     valueToUpdate->value = propValue.value;
     if (updateStatus) {
diff --git a/automotive/vehicle/2.0/default/impl/vhal_v2_0/EmulatedVehicleHal.cpp b/automotive/vehicle/2.0/default/impl/vhal_v2_0/EmulatedVehicleHal.cpp
index b76aff9..84354c1 100644
--- a/automotive/vehicle/2.0/default/impl/vhal_v2_0/EmulatedVehicleHal.cpp
+++ b/automotive/vehicle/2.0/default/impl/vhal_v2_0/EmulatedVehicleHal.cpp
@@ -127,7 +127,9 @@
             *outStatus = v != nullptr ? StatusCode::OK : StatusCode::INVALID_ARG;
             break;
     }
-
+    if (v.get()) {
+        v->timestamp = elapsedRealtimeNano();
+    }
     return v;
 }
 
@@ -305,6 +307,7 @@
         }
 
         if (v.get()) {
+            v->timestamp = elapsedRealtimeNano();
             doHalEvent(std::move(v));
         }
     }