According to the huge development space and capital needs of the urban rail transit industry，the PPP model will still be an important way of urban rail transit in terms of investment，construction and operation. In view of the problems of private part mismatch in PPP mode，this paper proposed two modes including pre-combination and post-combination，which are used to broaden the supplier scope of PPP mode，expand the cooperation mode of PPP and improve the operability of the project，and the practical application has been carried out in Shaoxing Rail Transit and X Rail Transit，thus providing the useful support for the development and innovation of the PPP model in the urban rail transit industry and has certain theoretical and practical significance.