The development and evolution of medical system in Japan was greatly influenced by Europe and America. But the Japanese medical system hadn’t been completely westernized in the Meiji Restoration period， neither had after World War Ⅱ. The Japanese medical system not only have absorbed the advanced Western experience， but also retained its own characteristics. This has a certain reference effect on China’s medical reform. This paper traced the medical reform history in Japan during different periods， and sumed up three characteristics of the medical reform in Japan including keeping the medical tradition during the westernization process， the smooth transition that had never hampered people’s lives； the benefit balance which was soughtby different medical institutions during the medical reform.