Abstract: As one of the most important public infrastructures, the safe operation of a power system is related to the national economy, the people's livelihood, and the economic and social stability. In recent years, some serious natural disasters around the world have led to severe blackouts, exposing the inadequacy of the power system's ability to deal with serious natural disasters. Strengthening the system resilience is a widely recognized means to enhance the disaster prevention and mitigation capabilities in the view of the academia and industry. In this paper, the concept of the power system resilience is first described. By comparing the difference between resilience and reliability, the emphasis of resilience assessment research is clarified. Then, based on literature research, the power system resilience assessment methods ever used are summarized, and the research status of the power system resilience framework and the key links based on the simulation method is specifically analyzed. Finally, based on the internal and external security risks faced by China's power grid, the difficulties and key technologies of the power system resilience assessment for severe natural disaster scenarios are prospected.