This paper aims to discuss the “extra-institutional political participation”，i.e.，the activities aim at influencing political process that go beyond or even transgress the established institutional framework，taken by farmers whose land has been expropriated by the government. Based on the case of three villages in suburban Beijing，the author argues that the insufficiency of institutional participation and the extent to which farmers’ interests are exploited by land-expropriation projects drive the affected farmer to extra-institutional participation. It is also argued that the level of their extra-institutional participation shows a clear positive correlation with the extent to which landless farmers organize themselves.