diff --git a/common/src/main/java/org/apache/uniffle/common/rpc/MonitoringServerTransportFilter.java b/common/src/main/java/org/apache/uniffle/common/rpc/MonitoringServerTransportFilter.java
index 2c29dd27a6..ef687ec416 100644
--- a/common/src/main/java/org/apache/uniffle/common/rpc/MonitoringServerTransportFilter.java
+++ b/common/src/main/java/org/apache/uniffle/common/rpc/MonitoringServerTransportFilter.java
@@ -37,7 +37,9 @@ public Attributes transportReady(Attributes transportAttrs) {
   }
 
   public void transportTerminated(Attributes transportAttrs) {
-    grpcMetrics.decGauge(GRPC_SERVER_CONNECTION_NUMBER_KEY);
+    if (transportAttrs != null) {
+      grpcMetrics.decGauge(GRPC_SERVER_CONNECTION_NUMBER_KEY);
+    }
     super.transportTerminated(transportAttrs);
   }
 }