diff --git a/core/api/src/main/java/org/onosproject/net/flow/instructions/Instructions.java b/core/api/src/main/java/org/onosproject/net/flow/instructions/Instructions.java
index e1a71fc..3e2335b 100644
--- a/core/api/src/main/java/org/onosproject/net/flow/instructions/Instructions.java
+++ b/core/api/src/main/java/org/onosproject/net/flow/instructions/Instructions.java
@@ -576,7 +576,7 @@
 
         @Override
         public String toString() {
-            return type().toString() + SEPARATOR + Integer.toHexString(groupId.id());
+            return type().toString() + SEPARATOR + "0x" + Integer.toHexString(groupId.id());
         }
 
         @Override