Population growth and agglomeration have provided an impetus for urban development, but which have brought great disturbance to the natural resource system, leading it to show the characteristics of vulnerability. In order to achieve sustainable development of population-natural resources, the government has implemented numbers of regulations and control policies in recent years. However, complex policies and their interactions on urban population-natural resource system are difficult to quantify in an accurate manner, which would increase the difficulty of balancing the relationship between urban population and natural resources. Therefore, this paper constructs a framework for evaluating the sustainability of population-natural resource system in Beijing. From the perspective of policy interventions, it analyzes the causal relationship between different types of regulatory policies ( such as population regulation, technical improvement, and resource control, etc. ) and population-natural resources. Meanwhile, it combined with the use of the Laplace criterion and the risk preferences of decision makers, to simulate the impact of mixed policy intervention on the sustainability of the population-natural resource system. The results show that: 1) Policy intervention is an important means to ensure the sustainable development of Beijing’s population-natural resources system. Population control policies are the main influencing factors for the change of Beijing’s population-natural resource system sustainability, while resource control and technological improvement are secondary factors; 2) As the intensity of policy interventions enhances, the sustainable level of population-natural resource in Beijing has gradually stabilized based on tradeoff between population system security and natural resource system fragility; 3) In Laplace scenario, population security decreased by 1. 82%, with a small loss. The vulnera- bility of natural resources decreased by 12. 13%, and the income was higher. Finally, the sustainability of the population-natural resource system was enhanced by 6. 23%. Therefore, policy intervention needs to take population security and natural resource vulnerability into consideration, rather than taking advantage of one and the other, so as to maximize the benefits of the popula- tion-natural resource system.