diff --git a/source/dnode/vnode/src/tsdb/tsdbRead2.c b/source/dnode/vnode/src/tsdb/tsdbRead2.c
index 880e73c5c0..9356973958 100644
--- a/source/dnode/vnode/src/tsdb/tsdbRead2.c
+++ b/source/dnode/vnode/src/tsdb/tsdbRead2.c
@@ -5827,9 +5827,12 @@ int32_t tsdbTakeReadSnap2(STsdbReader* pReader, _query_reseek_func_t reseek, STs
     pSnap->pIMem = pTsdb->imem;
     pSnap->pINode = taosMemoryMalloc(sizeof(*pSnap->pINode));
     if (pSnap->pINode == NULL) {
-      tsdbUnrefMemTable(pTsdb->mem, pSnap->pNode, true);  // unref the previous refed mem
       code = terrno;
 
+      if (pTsdb->mem && pSnap->pNode) {
+        tsdbUnrefMemTable(pTsdb->mem, pSnap->pNode, true);  // unref the previous refed mem
+      }
+
       (void) taosThreadMutexUnlock(&pTsdb->mutex);
       goto _exit;
     }