diff --git a/src/base/abci/abcResub.c b/src/base/abci/abcResub.c
index 803b88e91..f1f3ce04d 100644
--- a/src/base/abci/abcResub.c
+++ b/src/base/abci/abcResub.c
@@ -170,6 +170,9 @@ int Abc_NtkResubstitute( Abc_Ntk_t * pNtk, int nCutMax, int nStepsMax, int nMinS
     pManRes->nNodesBeg = Abc_NtkNodeNum(pNtk);
     nNodes = Abc_NtkObjNumMax(pNtk);
     pProgress = Extra_ProgressBarStart( stdout, nNodes );
+    //clear markB at the beginning
+    Abc_NtkForEachObj( pNtk, pNode, i )
+        pNode->fMarkB = 0;
     Abc_NtkForEachNode( pNtk, pNode, i )
     {
         Extra_ProgressBarUpdate( pProgress, i, NULL );