The application of PPP mode in urban underground utility tunnel project has been vigorously promoted and popularized in China. However, the degree of project promotion varies greatly in different regions, and the enthusiasm of social capital to participate in projects varies. In essence, the impact of project risks cannot be ignored. Using the fault tree model to analyze the factors that affect the risk of PPP mode in the urban underground utility tunnel project, and obtains five factors which have great influence on the risk of the project, such as the demand for corridor entrance, revenue, financial capacity, imperfect legal system, land expropriation and historical legacy. Considering the different economic development strengths of different regions, the adaptability of PPP projects is different. Through the empirical analysis of improving the correlation degree, the conclusion is drawn that the application of PPP model in underground comprehensive pipeline corridor is more suitable for developed areas.