This study investigates whether Key Audit Matters (KAMs) provide valuable information to the capital market and whether their disclosure increases investor-assessed risk or reduces uncertainty. The implementation of KAM disclosure aims to enhance the informational usefulness of audit reports. While a high number of KAMs described in an audit report could signal an increase in useful information, it might also indicate a greater number of audit issues within the company. This study, therefore, examines how investors evaluate the informational role of KAMs. First, our analysis reveals a significant negative relationship between the number of KAMs and the cost of equity. Second, this significant negative relationship was particularly pronounced in firms with a poor information environment. These findings suggest that the implementation goals of KAM disclosure are being achieved in practice. Furthermore, this study provides empirical evidence that KAMs play a crucial role in reducing uncertainty for information users in the capital market.