考虑到public private partnership（PPP）项目实际收益的不确定性，首先基于政府需求，通过引入项目运营收益的相对补偿指数，设计一种依赖特许收益的单期补偿契约；然后基于政府无法将私人投资变量纳入该契约，分别从集中决策与分散决策角度建立公私之间博弈模型来研究该契约的最优形式及其激励性与有效性，并给出政府有效补偿对策。研究表明：所得最优补偿契约既能激励私人选择政府集中决策时的最优初始投资，又能激励私人与政府共担风险、共享收益，但有效补偿还应满足项目社会效益约束，即对政府意味着有效补偿应适应项目实际不同情景。

In consideration of the uncertainty of PPP project benefit, firstly a relative index to describe the operating compensation for the project is introduced to design a single period compensation contract based on the government’s need. Then based on the fact that the private investment variable can’t be included in the contract, a game model between the public and private sector is proposed to explore the contact’s optimal form, incentive effect and valid condition respectively from the centralized and disperse decision-making. The research results show that the obtained optimal contract can encourage the private investor to choose the same optimal investment scale as the government’s centralized decision-making, and share both risks and revenues with the government. However, the valid compensation must satisfy the project’s social welfare constraint, which implies the valid compensation should be adapted to different actual scenes for PPP project.