Material strength is reduced by stress corrosion cracking (SCC), and SCC is considered one of the common failure modes. The prediction of the cracking path and cracking time is crucial for the structural strength design of engineering materials. Traditional numerical simulation methods for SCC are based on sharp interface models, such as electrochemical kinetic laws and diffusion theory. The diffusion characteristics of actual corrosion interfaces cannot be accurately described by these methods. In recent years, a diffuse interface is constructed by the phase-field method through the introduction of an order parameter. The numerical difficulty of explicitly tracking the interface is avoided, and the phase-field method is regarded as an effective means for simulating SCC. Recent scholarly discussions on strain energy in the phase-field method and the establishment of governing equations were introduced based on the phase-field model. Three stress corrosion theories, namely, the anodic film rupture theory, the hydrogen-induced cracking theory, and the crystal plasticity theory, were summarized. The application of the phase-field method to these three theories was presented. Finally, the problems existing in engineering applications of the model and the corresponding solutions are elaborated.