As an important part of the supervision system of the party and the state, financial and accounting supervision is of great significance in regulating enterprise behavior and preventing major financial risks. Taking A-share listed companies from 2017 to 2023 as research samples, and based on strengthening the pilot reform policy of financial and accounting supervision, this study constructs a Difference-in-Differences (DID) model to empirically evaluate the causal impact of national regularized financial and accounting supervision on corporate leverage manipulation. The study found that the regularized financial and accounting supervision can effectively inhibit the corporate leverage manipulation. Mechanism analysis shows that the regularized financial and accounting supervision can effectively inhibit the corporate leverage manipulation by exerting the deterrence effect and resource effect. Heterogeneity analysis shows that the inhibitory effect of the regularized financial and accounting supervision on the corporate leverage manipulation is more significant in sample enterprises with high book leverage ratio, large asset scale and low management shareholding ratio, as well as in sample enterprises located in areas with low financial development level. The test of economic consequences shows that the inhibitory effect of the regularized financial and accounting supervision on the corporate leverage manipulation helps to improve the total factor productivity of enterprises. The conclusion of this paper provides empirical evidence for regularized financial and accounting supervision to standardize corporate accounting behavior and prevent major financial risks in the market.