diff --git a/src/client/src/tscSQLParser.c b/src/client/src/tscSQLParser.c
index fabaa166e25a685fa314e2bc8086f878b5577bdc..9e8e780af7441529a6c99ffb56a934dd26f95c05 100644
--- a/src/client/src/tscSQLParser.c
+++ b/src/client/src/tscSQLParser.c
@@ -2023,6 +2023,8 @@ int32_t addExprAndResultField(SSqlCmd* pCmd, SQueryInfo* pQueryInfo, int32_t col
 
       if (!IS_NUMERIC_TYPE(colType)) {
         return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg1);
+      } else if (IS_UNSIGNED_NUMERIC_TYPE(colType) && optr == TK_DIFF) {
+        return invalidSqlErrMsg(tscGetErrorMsgPayload(pCmd), msg10);
       }
 
       int16_t resultType = 0;