This study investigates the effect of corporate governance on investment efficiency as well as the moderating role of audit quality in this regard in companies listed on the Tehran Stock Exchange. This research is applied in terms of purpose and descriptive-correlational in terms of research method. In other words, in this study, the existence of relationship and correlation between variables through regression is investigated. In order to achieve the above goal, three hypotheses were formulated. Based on this, in order to test the research hypotheses, a sample consisting of 108 companies listed on the Tehran Stock Exchange in the period 2014 to 2020 was selected. To test the research hypotheses, a multivariate regression model based on composite data was used. The results of this study show that there is a positive and significant relationship between corporate governance and audit quality on investment efficiency, which means that by increasing these criteria, investment efficiency will increase. Also, there is a positive and significant relationship between corporate governance and investment efficiency with the moderating effect of audit quality.