Abstract: This paper gives a detailed introduction to the Japanese health care system and medical insurance system, from the section of how public medical insurance works, the differences between social insurance and national health insurance, how medical expenses are paid,how national health insurance is maintained, how medical payment system works, and the health legislation and education system, which the Japanese are particularly proud of. Japan used to implement a voluntary national health insurance system. However, since the new national health insurance system was implemented in 1961, all of the voluntary insurance has become compulsory, which laid the groundwork to provide equal medical services to all citizens.

Key words: health care system, medical insurance, social insurance, national health insurance, Japan