Abstract: By means of SEM and AFM,the effects of surface morphology on corrosion resistance of 1Cr11Ni2W2MoV stainless steel in weak acid surrounding have been investigated.It is found that the corrosion resistance of the steel does not increase monotonously with the decrease of surface roughness,and the 1000# polished specimens show the best corrosion resistance,but the 800# polished specimens corrode more than the ground specimens.The main reason may be that the 1000# polished specimens have the highest metastable and stable pitting potentials,and the 800# polished specimens generate corrosive cells more easily than the ground specimens.