On the one hand, corporate tax avoidance increases corporate cash retention and retained earnings, and improves the sustainable operation capacity of enterprises. On the other hand, corporate tax avoidance，which is often associated with rent-seeking, reduces corporate transparency and weakens the quality of accounting information. So can auditors identify the impact of different types of corporate tax avoidance on the quality of accounting information? This paper takes Chinese listed companies as the research object and studies the relationship between the degree of corporate tax avoidance and modified audit opinion. We have the following findings:firstly, when the degree of client companies’ tax avoidance is low, as the corporate tax avoidance increases, the possibility of being issued modified audit opinions decreases. However, when the degree of client companies’ tax avoidance is high, with the increase in tax avoidance, modified audit opinions are more likely to be issued. Secondly, when auditors come from a large accounting firm, client companies are more likely to receive modified audit opinions in the highest quantile sample of tax avoidance. Thirdly, if the companies have higher shareholding of institutional investors, they are less likely to be issued modified audit opinions when their tax avoidance is low. The findings show that there is a non-linear relationship between corporate tax avoidance and audit opinion, and auditors can identify the impact of corporate tax avoidance of client companies on corporate value.