The project system has become a new governance mechanism in China and been diffused in public services.This paper mainly examines the modified project system in Shanghai cities based on the practice in China from the perspective of collaboration between the state and society.This paper develops a two-dimensional analysis framework of professionalization and openness in which “targeted projects”，“open projects”，“micro projects” and “sharing projects” are categorized as four basic types.Then，the author chooses several cases related in government procurement，innovative bidding，community micro projects and community public service complex in order to connect to previor theoretical studies and three core mechanisms，including separation，professionalization and bi-lateral cooperation.This paper displays that the contributions of four types projects to the revision of the project system by forming collaborations between the state and society through attracting social participation.Finally，the paper argues that the modified project system could be built into a platform for collaborative governance between the state and society.The key is its institutionalization.