[en] Austenitic stainless steels used for PWR core internal components degrade in the environment of radiation and high temperature water during their long-term service. As they suffer from intergranular cracking at the neutron fluence over the critical value, this degradation mechanism termed irradiation assisted stress corrosion cracking (IASCC) is one of the hot issues in light water reactor (LWR) industry to aim at pursuing license renewal of commercial reactors. Much attention has been paid to an understanding of the IASCC mechanism, which is yet to be achieved. IASCC appears to be very similar to intergranular stress corrosion cracking (IGSCC) in view of intergranular cracking but the former differs from the latter because the former can occur even without corrosion. Consequently, intergranular cracking of IASCC should be taken into account from mechanistic view points. The aim of this study is to analyze the IASCC susceptibility of austenitic stainless steels in view of material compositions and the environment, and hence to guide research directions to take in order to elucidate the IASCC mechanism