Abstract: The research on agricultural non-point source pollution control in Baiyangdian Lake has important practical significance for realizing comprehensive management and restoration of Baiyangdian ecology and building a beautiful new area of blue sky, green land and clear water. Aiming at the relative lack of quantitative research on agricultural non-point source pollution control in Baiyangdian, Xiong’an New Area, based on game theory, this paper constructed an evolutionary game model between government and farmers under public participation. On the basis of the amount of government punishment, the amount of subsidies and the cost of pollution reduction by farmers，two factors—the implementation of government environmental protection policies and the participation of public agricultural non-point source pollution control—were introduced innovatively, to make a more comprehensive study of the behavioral evolution characteristics of the game subject. It was found that the government’s implementation of punishment and the positive reduction of pollution by farmers are the ideal evolutionary state that the main body can achieve. The implementation of environmental protection policies of the New Area government, the increased participation of the public in agricultural non-point source pollution control, the increase in the amount of punishment of the New Area government, and the reduction in farmers’ pollution reduction costs will help farmers to move toward positive pollution reduction. This has an important impact on achieving the ideal steady state as soon as possible, ensuring water quality and realizing ecological restoration of Baiyangdian Lake. Based on this, this paper proposes to strengthen the New Area government’s supervision of the use of pesticides and fertilizers by farmers, attaches great importance to farmers’ mitigation costs to the Baiyangdian agricultural non-point source pollution control policy, and actively establishes public participation in the management mechanism of agricultural non-point source pollution control.