Abstract: With the arrival of an aging society, it is more and more important to accelerate the reform of China's pension insurance system. The development track of Japan's pension insurance system has similarities with that of China, and its main practice of system construction can provide reference for China. At present, China's pension insurance system still has problems such as insufficient government financial investment, fragmentation of pension insurance system, non-establishment of supplementary pension insurance system, and restrictions on pension investment. Suggestions to improve China's pension insurance are made on increasing government financial input into pension insurance, improving basic pension insurance standards for the entire population, establishing a multilevel pension insurance system, deepening the market operation of pensions, and promoting the construction of a long-term nursing insurance system.