This research aims to test the effect of deviation of institutional investors' attention on audit quality (with three criteria of going-concern audit opinions, Internal control weaknesses report, and restatement) It was done in the period of 2012 to 2021 and using the data of 132 companies admitted to the Tehran Stock Exchange, which were selected according to the systematic elimination method.. In order to carry out the hypotheses of the research, the Eviews 10 software and the logit regression method were used. Findings of this research shows that in case of lack of attention from institutional shareholders, auditor tendency to comment on continuity of the firms and reporting weak points of its internal controls decreases and the probability of restating of financial statements increases. That is, since institutional investors inattention are not able or interested to pay equal attention to all invested stocks at the same time and pay more attention to investments with abnormal returns and accordingly They pay little attention to investments with normal returns, this dual behavior of the aforementioned investors leads to the creation of a platform, the output of which is the reduction of audit quality.