Accountability is the basis for state audit to balance the power, promote democracy and act as the immune system of the whole country while the government audit department possesses great information power in accountability mechanism. As a breakthrough, this paper will further examine the nature of state audit. With strong information power and audit expertise, government audit department is able to provide information of high quality to related institutions in the information supply chain, through which state audit plays a role in national governance. Owing to its information property, state audit has mitigated information risks in economic, political and social level and promoted national governance effectively.