After the outbreak of COVID-19 in 2020，China implemented the largest social security “mitigation-free” policy in history in order to stabilize employment，alleviate the difficulties of enterprise social security contributions and promote the resumption of work and production after the epidemic. Meanwhile，the coverage of the social security system has steadily expanded and the size of the fund has continued to increase. This report summarizes the basic development of China’s social insurance business since 2020，sorts out the important reform measures of various social insurance systems，and provides an outlook on the future development trend of China’s social insurance system.