diff --git a/src/storage/ddl/ob_ddl_merge_task.cpp b/src/storage/ddl/ob_ddl_merge_task.cpp
index 87a3c3ec40..4125dd5e94 100644
--- a/src/storage/ddl/ob_ddl_merge_task.cpp
+++ b/src/storage/ddl/ob_ddl_merge_task.cpp
@@ -520,11 +520,11 @@ int ObTabletDDLUtil::prepare_index_data_desc(ObTablet &tablet,
 }
 
 int ObTabletDDLUtil::try_get_first_ddl_sstable(ObTablet &tablet,
+                                               ObTableStoreIterator &ddl_table_iter,
                                                blocksstable::ObSSTable *&first_sstable)
 {
   int ret = OB_SUCCESS;
   first_sstable = nullptr;
-  ObTableStoreIterator ddl_table_iter;
 
   ObITable *first_ddl_sstable = nullptr;
   if (OB_FAIL(tablet.get_ddl_sstables(ddl_table_iter))) {
diff --git a/src/storage/ddl/ob_ddl_merge_task.h b/src/storage/ddl/ob_ddl_merge_task.h
index 3e8e306ee1..e100191cf7 100644
--- a/src/storage/ddl/ob_ddl_merge_task.h
+++ b/src/storage/ddl/ob_ddl_merge_task.h
@@ -150,6 +150,7 @@ public:
                                      const blocksstable::ObSSTable *first_ddl_sstable,
                                      blocksstable::ObWholeDataStoreDesc &data_desc);
   static int try_get_first_ddl_sstable(ObTablet &tablet,
+                                       ObTableStoreIterator &ddl_table_iter,
                                        blocksstable::ObSSTable *&first_sstable);
   static int create_ddl_sstable(ObTablet &tablet,
                                 const ObTabletDDLParam &ddl_param,
diff --git a/src/storage/ddl/ob_tablet_ddl_kv.cpp b/src/storage/ddl/ob_tablet_ddl_kv.cpp
index 4d5f421ace..1be0f1ec2a 100644
--- a/src/storage/ddl/ob_tablet_ddl_kv.cpp
+++ b/src/storage/ddl/ob_tablet_ddl_kv.cpp
@@ -709,8 +709,9 @@ int ObDDLKV::close(ObTablet &tablet)
     ddl_param.start_scn_ = ddl_start_scn_;
     ddl_param.snapshot_version_ = snapshot_version_;
     ddl_param.data_format_version_ = data_format_version_;
+    ObTableStoreIterator ddl_table_iter; // need to hold first_sstable until finish
     ObSSTable *first_sstable = nullptr;
-    if (OB_FAIL(ObTabletDDLUtil::try_get_first_ddl_sstable(tablet, first_sstable))) {
+    if (OB_FAIL(ObTabletDDLUtil::try_get_first_ddl_sstable(tablet, ddl_table_iter, first_sstable))) {
       LOG_WARN("fail to get first sstable", K(ret), K(tablet));
     } else if (OB_FAIL(ObTabletDDLUtil::create_ddl_sstable(tablet, ddl_param, meta_array, first_sstable, allocator, sstable))) {
       LOG_WARN("create ddl sstable failed", K(ret), K(ddl_param), KP(first_sstable));