Under the PPP mode，some local governments lack effective control over the investments in the PPP projects resulting in many investments that are greedy for perfection or beyond the actual demand far. The reasons are not only the wrong understanding of the nature of the PPP project investment and the utility of investment control mechanism，but also the mismatch financial powers and expenditure responsibilities between the central government and local government. Under the background that the reform of central and local financial and administrative powers can not be accomplished overnight，relevant legislation should be adopted to establish an effective investment control mechanism for government infrastructure projects at first. Besides，regulating the decision-making behavior of local governments about constructions and investments，and establishing the specific rules of PPP mode with the core of the government decision-making process of PPP investment projects.