In the field of accounting, efforts should be made to reduce the delay in the auditor's report as much as possible. Therefore, the purpose of this study is to investigate the effect of sustainable management on the delay in the auditor's report, emphasizing the moderating role of the auditor's size and the quality of earnings. In this regard, 104 companies listed on the Tehran Stock Exchange were selected during the period 2015 to 2022. The research hypotheses were examined using mixed data and the statistical method of multiple regression and generalized least squares. Stata software was used to analyze the data. The findings of the study indicate a negative and significant effect of sustainable management on auditor report delay. The results also showed that auditor size has no effect on the relationship between sustainable management and auditor report delay, while earnings quality has a negative and significant effect on the relationship between sustainable management and auditor report delay. Therefore, corporate sustainable management can, as a factor that reduces audit risk from the external auditor's perspective, reduce the perception and delay in the audit report due to less time spent on the audit. Also, considering the moderating role of earnings quality, this variable can be considered an important variable in the relationship between corporate sustainable management and auditor report delay.