diff --git a/source/libs/executor/src/tsort.c b/source/libs/executor/src/tsort.c
index 6fe7e73f77..272629627a 100644
--- a/source/libs/executor/src/tsort.c
+++ b/source/libs/executor/src/tsort.c
@@ -1573,7 +1573,7 @@ static int32_t sortBlocksToExtSource(SSortHandle* pHandle, SArray* aBlk, SArray*
     }
 
     blkPgSz += bufInc;
-    ASSERT(blkPgSz == blockDataGetSize(pHandle->pDataBlock));
+    ASSERT(blkPgSz == blockDataGetSize(pHandle->pDataBlock) + pgHeaderSz);
 
     ++nRows;