The Beijing-Tianjin-Hebei region of China experiences overexploitation of groundwater (GW), mainly through agricultural water use. Planting structure adjustment (PSA) has proved to be effective in controlling GW use, although this inevitably affects the stakeholders. An ecological protection compensation (EPC) policy has been implemented simultaneously with PSA to meet the compensation needs of those who have lost profits. However, problems in policy design and implementation resulted in insufficient sustainability of the EPC. This study aimed to resolve these problems fundamentally by improving the current policy, based on the analysis of the interactions among the central government, the local government, and the farmers. Firstly, a mechanism for implemented economic penalties for violations was introduced. Secondly, the long-term interests and respective characteristics of all parties were taken into consideration. Finally, a tripartite evolutionary game model was established. Analysis based on evolutionary game theory allowed calculation of the constraints of the parameters in the model, which can drive the model to evolve in the expected direction. Under these constraints, the numerical simulations showed that: 1) information asymmetry should be minimized as much as possible during policy implementation; 2) reducing costs can accelerate self-convergence, but will not affect other participants; 3) the implementation of economic penalties can promote the evolution of the supervised party to evolutionary stability strategy; 4) improving the level of effort by farmers in implementing the policy is key to accelerating the evolution of the entire system.