diff --git a/core/src/main/scala/org/apache/spark/storage/memory/MemoryStore.scala b/core/src/main/scala/org/apache/spark/storage/memory/MemoryStore.scala
index 586339a58d236..32f1c23a05e58 100644
--- a/core/src/main/scala/org/apache/spark/storage/memory/MemoryStore.scala
+++ b/core/src/main/scala/org/apache/spark/storage/memory/MemoryStore.scala
@@ -273,7 +273,7 @@ private[spark] class MemoryStore(
           blockId, Utils.bytesToString(size), Utils.bytesToString(maxMemory - blocksMemoryUsed)))
         Right(size)
       } else {
-        assert(currentUnrollMemoryForThisTask >= currentUnrollMemoryForThisTask,
+        assert(currentUnrollMemoryForThisTask >= unrollMemoryUsedByThisBlock,
           "released too much unroll memory")
         Left(new PartiallyUnrolledIterator(
           this,