Abstract: The research advances in crack propagation behavior of stress corrosion cracking (SCC) in structural materials of nuclear reactors are introdnced. The effects of hydrochemical, mechanical and material factors on the crack propagation behavior of SCC are summarized. The influence mechanism of different influencing factors on crack propagation based on the slip-dissolution-oxidation model is explained, furthermore, the trend of further research of SCC crack propagation behavior is predicted.