Based on the unique institutional scenario of the Shanghai and Shenzhen Stock Exchanges staggered issuance of information disclosure guidelines for listed companies by industry,this paper empirically tests the impact of disclosure by industry on the auditor choice. The difference-in-difference model result shows that companies affected by the sub-industry information disclosure policy are more likely to hire auditors with industry expertise than unaffected companies after the implementation of the policy. Moreover, this effect is more pronounced in non-state-owned companies. Further analysis shows that,industry operational information disclosure prompted enterprises to hire more auditors with industry expertise, significantly improved the audit quality, and reduced the audit cost and audit delay. The conclusions provide incremental empirical evidence for the impact of information disclosure system changes on corporate auditing behavior, and also have an enlightening effect on the in-depth understanding of the development and evolution of China’s audit market structure.