Based on the provincial panel data of China from 2007 to 2020, this paper studies the relationship between national audit and government budget execution performance and its mechanism. From the empirical point of view, this paper verifies the role of state audit in improving the performance of government budget execution. It is found that the performance of government budget execution has spatial autocorrelation characteristics, and the influence of state audit on the performance of government budget execution has positive spatial spillover effect. National audit has promoted the improvement of government budget performance from two direct and indirect paths, and government efficiency and market environment have played a dual intermediary role in this indirect path; In 2013, the national local government debt audit had an obvious event impact effect on the performance of government budget implementation.