Improving the efficiency of local fiscal expenditure is an important way to swiftly mitigate local fiscal risks according to the current economic situation. Based on the provincial panel data of 30 provinces in mainland China (except Tibet Autonomous Region) from 2007 to 2018, a Tobit spatial error model was constructed to test the impact of national auditing on local fiscal expenditure efficiency and to investigate the intermediary role of media attention. Findings show that the disclosing, resisting, and preventing functions of the national audit significantly improve local fiscal expenditure efficiency. Media attention does play an intermediary role, indicating that the information transmission function of the national audit has governance effects. Coupling of the national audit and media attention also positively affects local fiscal expenditure efficiency. This research expands the mechanism of national audits, as they affect the efficiency of local fiscal expenditure; it also provides new empirical evidence for improving such efficiency while mitigating fiscal risks at the local level.