Based on the corporate values and agency views of tax avoidance,using A-share listed companies from 2010 to 2021 as research samples,this paper empirically examines the impact of corporate tax avoidance on auditor decision-making.Re-search has found that there is a non-linear relationship between corporate tax avoidance and auditor decision-making,with a U-shaped relationship between tax avoidance and audit pricing,as well as between tax avoidance and audit opin-ions.In addition,internal control has a significant moderating effect on the U-shaped curve of tax avoidance and audit pricing.The improvement of internal control quality makes the U-shaped curve more steeper and the turning point shifts to the right,delaying the turning point of audit pricing decisions;The improvement of the external institutional environ-ment has made the U-shaped curve between tax avoidance and audit pricing,as well as between tax avoidance and audit opinions,more steep and the turning point shifted to the left.With the continuous improvement of the external institution-al environment,the turning point of auditor decision-making has advanced.The research conclusion of this article pro-vides theoretical support for auditors to make scientific decisions and avoid risks,and also provides useful insights for en-terprises to establish correct tax avoidance concepts.