Compared with traditional model of designconstruction, the market subjects under PPP model may have strong vulnerability. However, the research on PPP market subjects’ vulnerability is few. Hence, the paper focuses on related research review of the vulnerability to specify the research field of the vulnerability. Based on the thinking way of vulnerability connotationformation mechanismdiffusion mechanismappraisal early warning, the paper analyzes the present literature of enterprises’ vulnerability, projectoriented enterprises’ vulnerability and projectoriented enterprises’ vulnerability under PPP model. The research shows that the shortage of the study of the formation of projectoriented enterprises’ vulnerability and diffusion mechanism obstructs the research development of the appraisal and early warning of projectoriented enterprises’ vulnerability, which has impact on research foundation under PPP model. Therefore, it proposes the related theories on formation mechanism and diffusion mechanism and corresponding mathematical model of projectoriented enterprises’ vulnerability and then looks forward to the future research of projectoriented enterprises’ vulnerability under PPP model.