diff --git a/core/src/main/scala/org/apache/spark/util/JsonProtocol.scala b/core/src/main/scala/org/apache/spark/util/JsonProtocol.scala
index b0754e3ce10db..c4dddb2d1037e 100644
--- a/core/src/main/scala/org/apache/spark/util/JsonProtocol.scala
+++ b/core/src/main/scala/org/apache/spark/util/JsonProtocol.scala
@@ -205,7 +205,6 @@ private[spark] object JsonProtocol {
   }
 
   def taskInfoToJson(taskInfo: TaskInfo): JValue = {
-    val accumUpdateMap = taskInfo.accumulables
     ("Task ID" -> taskInfo.taskId) ~
     ("Index" -> taskInfo.index) ~
     ("Attempt" -> taskInfo.attempt) ~