Abstract: The second green belt country park ring is an important green carrier to coordinate urban development and natural environment in Beijing. It is also an effective way to meet the recreational needs of the public and provide urban security. This research explores the theoretical connotation and research process of the scenario analysis in the planning course. Based on the complexity and uncertainty of ecological environment, service object and functional bearing in the construction of the second green belt country park ring, it proposes to conduct a scenario planning study. Firstly, establish a basic scenario for the implementation of Beijing Urban Master Plan (2016—2035) for the basic construction of the second green belt. Secondly, carry out quantitative analysis guided by the three goals of ecology, recreation and safety, around the four key factors of habitat quality, carbon sequestration and oxygen release, recreation services, and urban stormwater. Combined with the basic scenario, it conducts a multi-object-oriented country park ring planning simulation and comprehensive analysis. This research provides new strategies for integrated scientific construction of the country park ring in the context of coordinated development of the city and nature. It also furnishes new thinking perspectives for the planning of complex and unpredictable green space systems.