Public participation in the governance of the state has increasingly become an important part of the national governance system. In this paper, the function of public participation in the process of national governance could be abstracted into public utility constraints in the framework of political economics, and the public utility constraint mechanism is clarified by constructing a simple local public expenditure structure selection model. Based on the economic impact of Chinas local developmental government behavior under the soft constraints of the public utility and the problems encountered to directly construct the public utility constraint mechanism, the paper offers a relational explanation for the governance logic of the central government to strengthen the national audit. It is pointed out that the supply of audit system can be improved from the aspects of audit methods and procedures, audit engagements and audit results application so as to comprehensively evaluate the utility result, deeply fit the utility goal and effectively implement the accountability constraint and thus realize construction of the public utility constraint mechanism indirectly. As the internal regular incentive and restraint mechanism of public power governance, the Chinese government audit can better adapt to the needs of national governance with certain institutional background at the current stage of development.