Based on the theory of protection motivation，environmental risk perception is divided into four dimensions：fact perception，cause perception，loss perception and reaction behavior perception.Using 839 field survey data from Jiangsu and Anhui provinces，structural equation model is used to explore the impact mechanism of multi-dimensional environmental risk perception on people’s pro-environmental behavior in the public sphere.The results show that different dimensions of environmental risk perception have different impacts on people’s pro-environmental behavior in the public sphere，with reaction behavior perception having a significant positive impact on people’s pro-environmental behavior in the public sphere，and responsibility consciousness playing an intermediary role in the impact of environmental risk perception on people’s pro-environmental behavior in the public sphere.Specifically，fact perception and cause perception have no direct or indirect impact on people’s pro-environmental behavior in the public sphere.What’s more，loss perception has no direct impact on pro-environmental behavior in the public sphere，but it can have an indirect impact through the sense of responsibility and reaction behavior perception can also have an indirect impact on pro-environmental behavior in the public sphere through responsibility consciousness.Therefore，it is feasible to guide people to practice pro-environmental behavior in the public sphere through strengthening environmental cognitive education，stimulating environmental emotion and cultivating sense of responsibility so as to build a modern environmental governance system with the participation of all the people.