diff --git a/src/sql/engine/sort/ob_sort_op_impl.cpp b/src/sql/engine/sort/ob_sort_op_impl.cpp
index 8c2e421d3b4ce497e562f1cccf71ae13e789c452..c27625697609778eef85ea949b051140a7509ad1 100644
--- a/src/sql/engine/sort/ob_sort_op_impl.cpp
+++ b/src/sql/engine/sort/ob_sort_op_impl.cpp
@@ -617,8 +617,8 @@ int ObSortOpImpl::init(
         default_block_size))) {
       LOG_WARN("init row store failed", K(ret));
     } else if (batch_size > 0
-               && NULL == (stored_rows_ = static_cast<ObChunkDatumStore::StoredRow **>(
-                       mem_context_->get_arena_allocator().alloc(
+               && OB_ISNULL(stored_rows_ = static_cast<ObChunkDatumStore::StoredRow **>(
+                       mem_context_->get_malloc_allocator().alloc(
                            sizeof(*stored_rows_) * batch_size)))) {
       ret = OB_ALLOCATE_MEMORY_FAILED;
       LOG_WARN("allocate memory failed", K(ret));
@@ -699,6 +699,10 @@ void ObSortOpImpl::reset()
       mem_context_->get_malloc_allocator().free(ems_heap_);
       ems_heap_ = NULL;
     }
+    if (NULL != stored_rows_) {
+      mem_context_->get_malloc_allocator().free(stored_rows_);
+      stored_rows_ = NULL;
+    }
     if (NULL != buckets_) {
       mem_context_->get_malloc_allocator().free(buckets_);
       buckets_ = NULL;