The application and development of PPP has promoted the marketization development of environment protection sector significantly. However，there are significant differences in terms of the nature of risks and demands for business model in different segments of the environment protection sector，resulting in different degrees and effectiveness of the implementation of PPP in different segments. This report summarizes the implementation modes of market-oriented projects in the field of environment protection during the 13th Five-Year Plan period. The differences of risk natures in different segments were compared. And the applicability of PPP in different segments were summarized. Aimed to provide detailed background references for implementing PPP in the environment protection sector.