SYNOPSIS Using Chinese data of key audit matters (KAM) reports, this study assesses whether the KAM rule improves audit quality and how KAM disclosures relate to audit quality. With textual analysis, we evaluate disclosure characteristics in detail and find that auditors report both industry-generic and firm-specific KAM. The wordings, to a large extent, are firm-specific and differ in KAM reporting components. Our empirical investigation via the pre-post and difference-in-differences analyses reveals that audit quality is improved following the mandatory rule. The cross-sectional analysis shows that the number of KAMs and disclosure characteristics (such as specificity, similarity, readability, and length) signal auditors' concern about clients' earnings quality, audit effort, and the propensity of issuing modified opinions. Overall, our paper provides some evidence on the implementation and communicative value of the new KAM reporting. Data Availability: Data are available from the public sources cited in the text. JEL Classifications: M41; M42; M48.