Social risk is the premise of the existence of the social insurance system. Without social risks, there will be no social insurance. Starting from the related concepts of risk, risk society and social risk, this paper comprehensively expounds the social risk generation and its development path in the social insurance system, and finds that the social risk dealt with in the social insurance system is a moderately dangerous risk accident with its own specific institutional connotation. On this basis, the paper analyzes the principles, mechanisms and advantages of the social insurance system’s response to social risks from two perspectives: the insurance principle as a technical approach and the right to social security.