diff --git a/hadoop-hdds/framework/src/main/java/org/apache/hadoop/hdds/utils/db/RDBMetrics.java b/hadoop-hdds/framework/src/main/java/org/apache/hadoop/hdds/utils/db/RDBMetrics.java
index d5d1f3657bf0..e4140c43c216 100644
--- a/hadoop-hdds/framework/src/main/java/org/apache/hadoop/hdds/utils/db/RDBMetrics.java
+++ b/hadoop-hdds/framework/src/main/java/org/apache/hadoop/hdds/utils/db/RDBMetrics.java
@@ -101,7 +101,7 @@ public long getNumDBKeyMayExistMisses() {
     return numDBKeyMayExistMisses.value();
   }
 
-  public static void unRegister() {
+  public static synchronized void unRegister() {
     instance = null;
     MetricsSystem ms = DefaultMetricsSystem.instance();
     ms.unregisterSource(SOURCE_NAME);