diff --git a/src/query/src/qAggMain.c b/src/query/src/qAggMain.c
index e4ef74a74dce416085f3b796147150886658c456..4dcb88ed3ac82eb05606d59dae5038b445611cd1 100644
--- a/src/query/src/qAggMain.c
+++ b/src/query/src/qAggMain.c
@@ -4651,7 +4651,7 @@ static void mavg_function(SQLFunctionCtx *pCtx) {
 
       ++notNullElems;
       pCtx->pOutput += pCtx->outputBytes;
-      pCtx->ptsOutputBuf++;
+      pTimestamp++;
     }
 
     ++mavgInfo->pos;