The ability of the auditor industry expertise to play an external governance role has been controversial in academic circles. This study empirically analyzes the impact of auditor industry expertise on corporate violations and explores the mechanisms through which it affects corporate violations, using a research sample of A-share listed companies in China from 2012 to 2022. The findings indicate that auditor industry expertise significantly suppresses corporate violations, and this conclusion holds steady after conducting a series of robustness tests. The mechanism analysis indicates that auditors with industry expertise can inhibit corporate violations through two channels: reducing agency cost and mitigating information asymmetry. Further research finds that client importance enhances the inhibitory effect of auditor industry expertise on corporate violations. The research in this paper not only expands the literature on the governance effects of auditors with industry expertise, but also provides some lessons for regulators, accounting firms and investors.