The existence of ESG rating disagreement brings certain decision-making problems to creditors, but it also prompts enterprises to "self-help". This "self-help" behavior may alleviate the information asymmetry between enterprises and creditors, enhance the development potential of enterprises, and thus reduce the cost of enterprise debt financing. Based on the panel data of Chinese listed companies from 2009 to 2022 the impact of ESG rating disagreement on debt financing costs and their mechanism was explooed. The results show that ESG rating disagreement sgnificantly reduces the cost of corporate debt financing, which is still established after a series of robustness tests and endogeneity treatments, such as double clustering, subsample regression, PSM propensity score matching, quasi natural experiments, etc. Mechanism analysis shows that ESG rating disagreement reduces debt financing costs by forcing enterprises to improve the quality of ESG information disclosure, green innovation level and attract the attention of analysts. Heterogeneity analysis founds that ESG rating disagreement has a more obvious effect on reducing the debt financing costs of high-polluting enterprises and enterprises with poor regional financial ecological environment. The economic consequences shows that ESG rating disagreement increases the market value of enterprises, resulting in higher market development capabilities for enterprises. It reveals the economic consequences of ESG rating disagreement from the perspective of debt financing costs, enriches the connotation of ESG rating disagreement, and is of great significance for the urgent need to unify ESG rating standards and how to unify them.