According to the new audit reporting standards, auditors need to disclose risk information in key audit matters. Whether the external perception of the information is a kind of “risk control” or “risk spillover” is a theoretical proposition that needs to be tested. Therefore, taking A-share listed companies from 2017 to 2021 as the research object, the impact of risk information disclosure on debt financing costs is investigated through the risk word frequency of statistical texts. The results show that the disclosure of risk information in the disclosure of key audit matters significantly reduces the cost of debt financing and supports the expectation of information view. Further research shows that risk disclosure of key audit matters affects debt financing costs mainly by alleviating information asymmetry and reducing debt default risk; In the sub-samples with higher agency cost and lower banking competition, the disclosure of risk information of key audit matters has a more obvious effect on reducing debt financing cost. This not only provides incremental empirical evidence for the effect of the new audit report reform, but also has certain reference value for promoting the implementation of the standards and improving the regulatory rules system of the capital market.