Abstract: This paper analyzes the neutron penalty and advantage of the candidate accident–tolerant cladding materials 304 SS, 310 SS, FeCrAl, APMT and SiC. The results show that the sequence from high to low is: SiC＞Zr＞FeCrAl＞APMT＞304SS＞310SS. After using a thinner cladding of 0.4 mm and keeping a constant outer diameter, Fe-based alloys require an increase of no more than 0.5%, for achieving the same fuel cycle length [about 60000 MW·d/t（U）] as the zircaloy’s, while Si C requires less enriched uranium about 0.12% by using a standard cladding thickness.