Using imbalanced panel data from Chinese commercial banks from 2008 to 2020, examine the impact of national auditing on bank credit behavior. Research has found that national auditing can promote banks to provide more lenient credit, and this effect has continuity. Mechanism analysis shows that national auditing can promote bank credit expansion through three channels: improving management efficiency, reducing violations, and increasing economic growth. Heterogeneity analysis shows that national auditing has a more significant positive impact on credit behavior of banks with good internal governance, located in the eastern region, and a better external legal environment. The moderating effect indicates that social auditing enhances the promoting effect of national auditing on bank credit, while media supervision weakens the effect of national auditing, while the moderating effect of public supervision is not significant. Further research indicates that although national auditing promotes bank credit disbursement, it has a restraining effect on loan concentration. Compared to commercial loans and non farm loans, national auditing enhances consumer loans and farm loans. The relationship between national auditing and bank credit reduces nonperforming loan ratios and improves bank financial performance, indicating that national auditing can promote the highquality development of bank credit business.