Abstract: This study investigated the effect of audit committee characteristics on the performance of firms listed in the Iraqi Stock Exchange. The study specifically evaluates the impacts of the audit committee knowledge, audit committee existence and audit committee independence on firm performance. A secondary data from a list of company are presented in ISX from 2012-2015 was used to evaluate the relationship between the dependent and independent variables. The independent variables considered are audit committee knowledge, audit committee existence and audit committee independence while the ROA is used to measure the firm performance as the dependent variable from the secondary data collected. The study showed that by using ROA there is significantly positive association between audit committee existence, audit committee independence and firm performance. However, it is revealed that there is also significantly negative association between firm performance and audit committee knowledge. The study reached a conclusion that firm performance is improved by audit committee independence and audit committee existence. The results of this study can be used by the decision and policy makers to establish a reliable relationship between agency and the principal.