Semnan University International Journal of Nonlinear Analysis and Applications 2008-6822 17 1 2026 01 01 The effect of the characteristics of internal audit performance and the characteristics of the audit committee on the quality of internal control 51 66 9351 10.22075/ijnaa.2022.28839.4004 EN Ali Malekimehr Department of Accounting, Qaemshahr Branch, Islamic Azad University, Qaemshahr, Iran Ali Jafari Department of Accounting, Qaemshahr Branch, Islamic Azad University, Qaemshahr, Iran Abbasali Puraghajan Department of Accounting, Qaemshahr Branch, Islamic Azad University, Qaemshahr, Iran Journal Article 2022 09 17 This research investigates the relationship between the audit committee's activities and the audit committee's characteristics on the quality of the internal control system in companies admitted to the Tehran Stock Exchange. The current research was semi-experimental regarding practical purpose and data collection method. To analysis the data from the panel data fan, it was done in the period of 2013-2017. The statistical software used was Eviews and the statistical population of the research was all the companies accepted in the Tehran Stock Exchange. The results of the research showed at the 95% confidence level that there is a significant relationship between the size of the audit committee and the type of audit institute with the quality of internal control. Also, the number of members of the audit committee has a significant relationship with the quality of internal control (weakness at the general level) and finally, the type of audit institution has a relationship between the activities of the audit committee (the number of members of the audit committee) and the quality of internal control (weakness at the general level and weakness at the income level). According to the results obtained from the hypothesis test, it can be concluded that the size of the audit committee and the type of audit institution are effective on the quality of internal control, but considering the number of members of the audit committee, this effect has not been effective on the internal control criteria and its indicators. It is suggested that the number of members of the audit committee be increased and stricter laws be adopted to oblige all companies to have an audit committee. https://ijnaa.semnan.ac.ir/article_9351_309de544dc40880ca6eb4bbcaa3e4ab3.pdf