diff --git a/external/avro/src/main/scala/org/apache/spark/sql/avro/AvroDeserializer.scala b/external/avro/src/main/scala/org/apache/spark/sql/avro/AvroDeserializer.scala
index 50db6348923c..2c17c16f06da 100644
--- a/external/avro/src/main/scala/org/apache/spark/sql/avro/AvroDeserializer.scala
+++ b/external/avro/src/main/scala/org/apache/spark/sql/avro/AvroDeserializer.scala
@@ -167,13 +167,14 @@ class AvroDeserializer(rootAvroType: Schema, rootCatalystType: DataType) {
       case (ARRAY, ArrayType(elementType, containsNull)) =>
         val elementWriter = newWriter(avroType.getElementType, elementType, path)
         (updater, ordinal, value) =>
-          val array = value.asInstanceOf[java.util.Collection[Any]]
-          val len = array.size()
-          val result = createArrayData(elementType, len)
+          val collection = value.asInstanceOf[java.util.Collection[Any]]
+          val result = createArrayData(elementType, collection.size())
           val elementUpdater = new ArrayDataUpdater(result)
 
           var i = 0
-          for (element <- array.asScala) {
+          val iter = collection.iterator()
+          while (iter.hasNext) {
+            val element = iter.next()
             if (element == null) {
               if (!containsNull) {
                 throw new RuntimeException(s"Array value at path ${path.mkString(".")} is not " +