Abstract : It has been widely recognized that poor health is an important cause of poverty, especially among the low- and middle- income countries. One of the reasons is the absence of public financial protection against the medical consumption risk in these countries. This Phd dissertation is dedicated to discern the role that health insurance could play in the organization of health financial protection system. The dissertation is composed of two parts. The first part discusses the problems linking to the financing to medical consumption from a global point of view. Chapter 1 brings theoretical discussions on three topics: 1) the specialties of medical consumption risks and the difficulties in using private health insurance to manage medical consumption risks. 2) The role of government and market in the distribution of health resources. 3) The options for the organization of health financing system. Chapter 2 conducts a statistical comparison on the performance of health financing systems in the countries of different social-economic background. The discussion is carried out around three aspects of health financing: the availability of resources, the organization of health financing, and the coverage of financial protection. The second part of the dissertation studies the evolution of heath financing system in a specific country: China. Three chapters are assigned to this part. Chapter 3 introduces the history of Chinese health financing system since 1950s. It helps us to understand the challenges in health financing brought by economic reform. Chapter 4 carries out an empirical study on the distribution of health financing burden in China in the 1990s. It illustrates the direct results of the decline of public financing and increase of direct payment. Chapter 5 presents health insurance reform that launched by the government since the end of 1990s. An impact analysis is conducted on an original dataset of 24 township hospitals in Weifang prefecture in the north of the China. The objective is to estimate the impact of the implementation of New Rural Medical Cooperation System (NRMCS) on the activities and financial structure of township hospitals. At last, we conclude that social health insurance (SHI) permits a sharing of health financial responsibilities between the service provider, the patient-consumer, and the service purchaser. It can not only involve both public and private agents into the collection of funds for health financing system, but also make each party more accountable due to the risks they bear from the result of medical consumption. Meanwhile it is necessary to note that SHI is just one option among others to organize health financing system. The implementation of SHI requires a certain level of social-economic development. SHI does not systematically bring better performance on health financing if it is not accompanied by the reforms on provider payment or on service delivery system. Government commitment and institutional capacity are also key factors for the good function of the system.