Health insurance is recognized as a worldwide problem. with the development, people pay more and more attention to health. Medical insurance to protect people's health as one of the principal means of caused wide attention. Medical care insurance is an important component of social guarantee system in China. It can improve living standard, and realization of social economical sustainable development and building a modest affluence and harmony. But with the development of society, the existing medical insurance mechanism show many disadvantages, and can't meet the needs of the people, so to medical insurance system reform of medical treatment system, the success of the medical insurance system reform is not only related to each person's vital interests, to Chinese health career as well as the development of the society in all have very important significance. So it is important to improve the reform of the medical insurance system. Continue to promote the reform of the medical insurance system, to develop a scientific and comprehensive medical insurance system. To realize highest medical services for all the people is an important work. The thesis is composed of six parts in all. The first part is the introduction part, analyzed the research purpose, method and structure; the second part is the analysis of the background for the medical insurance system; the third part is about the China medical insurance system; the fourth part is the analysis on several foreign medical insurance system; the fifth part is the summary of China medical insurance system problems and put forward the improvement scheme; the final part is the conclusion of this thesis.