diff --git a/src/query/src/qFilter.c b/src/query/src/qFilter.c
index 471c6a9167117a0b2eca5726043508d3984a1bc7..d8e1d5ac5d06db15d28fe68cf5470e178a8addac 100644
--- a/src/query/src/qFilter.c
+++ b/src/query/src/qFilter.c
@@ -860,6 +860,7 @@ int32_t filterAddFieldFromNode(SFilterInfo *info, tExprNode *node, SFilterFieldI
   if(node->nodeType == TSQL_NODE_EXPR && node->_node.optr == TSDB_RELATION_ARROW){    // json tag -> operation
     type = FLD_TYPE_COLUMN;
     assert(node->_node.pRight->pVal->nLen < TSDB_COL_NAME_LEN);
+    memset(node->_node.pLeft->pSchema->name, 0, TSDB_COL_NAME_LEN);
     strncpy(node->_node.pLeft->pSchema->name, node->_node.pRight->pVal->pz, node->_node.pRight->pVal->nLen);
     v = node->pSchema;
     node->pSchema = NULL;
diff --git a/src/tsdb/src/tsdbRead.c b/src/tsdb/src/tsdbRead.c
index f5cc4499fe4ee2005c8b6b024f8cdc74cb28aa54..66c8719f86269d71ddd05fbee6b14edf6dcd2804 100644
--- a/src/tsdb/src/tsdbRead.c
+++ b/src/tsdb/src/tsdbRead.c
@@ -4109,7 +4109,20 @@ static void queryByJsonTag(STable* pTable, void* filterInfo, SArray* res){
     SFilterField* fi = &info->fields[FLD_TYPE_COLUMN].fields[i];
     SSchema*      sch = fi->desc;
     if (sch-> colId == TSDB_TBNAME_COLUMN_INDEX) continue;
-    SArray** data = (SArray**)taosHashGet(pTable->jsonKeyMap, sch->name, strlen(sch->name));
+    int32_t outLen = 0;
+    char* key = NULL;
+    if(JSON_TYPE_NCHAR){
+      char tagKey[256] = {0};
+      if (!taosMbsToUcs4(sch->name, strlen(sch->name), tagKey, 256, &outLen)) {
+        tsdbError("json key to ucs4 error:%s|%s", strerror(errno), sch->name);
+        return;
+      }
+      key = tagKey;
+    }else{
+      key = sch->name;
+      outLen = strlen(sch->name);
+    }
+    SArray** data = (SArray**)taosHashGet(pTable->jsonKeyMap, key, outLen);
     if(data == NULL) continue;
     if(tabList == NULL) {
       tabList = taosArrayDup(*data);