The features of legal system of national health insurance in Japan are exclusive, like social security, elderly people is high rate, medical care system of retired employee is included, medical care system of elderly people is connected with national health insurance, national health insurance and care insurance system are carried out side by side. In distribution of authority of national health insurance, lots of these are belonged to the country in principle, but the execution of these are country & self-government, there are also belonged to the local government at the same time. The further, the funding is from health insurance fee (or tax), national treasury,and cost sharing.