Abstract: Public cultural service system construction is a hot topic in the fields of theoretical research and government practices. The academic research, central file and local practice all emphasis the importance of guiding and encouraging social forces to participate in the public culture service. Based on the analytic frame of role separation，the paper firstly sets up cooperator，donator，initiator and operator as the four role types of private enterprise，and then analyzes the role realization and restriction mechanism of private enterprises under the government-enterprise relationship network to provide research framework for further study