Abstract: Group organization participation in government procurement of public services is not only an important means to be actively involved in social governance, but also an important driving force for the development of social organizations. The paper summarizes the innovation cases of group participation in government's purchase of public service, which is of great significance for the promotion of mass reform experience. Taking the group reform of Chongqing Municipality as the object of the case study, the paper describes the participatory structure, participation mode and practical innovation of the group participation in the government purchase of public service. To solve the problems of imperfect purchase method, scarce purchase content, single source of support resource, the paper puts forward some suggestions like guiding in accordance with the law, establishing more comprehensive purchase list, increasing the support of purchase resources, and creating public service platform.