As the external consultant of government and social capital，PPP consulting institution plays an important role in providing high-quality professional services in the project life cycle of PPP during identification，preparation，procurement，implementation and transfer. While PPP “post consultation” serves the long project process from implementation to transfer，PPP “pre consultation” only solves the problems from project identification to procurement in the perspective of time sequence，including drawing up the PPP project implementation plan，value for money，argument of financial affordability etc. An effective implementation depends on the project construction，investment and operation within over ten years’ cooperation. The “post consultation” is able to audit and supervise the compliance，project quality etc. at each stage，as well as prevent from the lack of controlling in order to ensure the project operating with high-quality.