The aim of this study was to investigate the impact of corporate governance mechanisms on financial performance considering the moderating role of earnings quality in companies listed on the Iraq Stock Exchange. In this research, data for testing the study hypotheses were collected from the Central Bank of Iraq, audited financial statements of companies listed on the Baghdad Stock Exchange, and the official website www.isx-iq.net. The statistical population consisted of all companies listed on the Baghdad Stock Exchange during the period from 2016 to 2021. Systematic elimination sampling was used for sample selection. Statistical analysis to estimate the research model was conducted using multiple regression. For this purpose, Excel and EViews software were used, and the models were estimated through random effects, fixed effects panel data methods, as well as ordinary least squares (OLS). Based on the data from Iraqi listed companies, hypotheses one through six were confirmed. The results showed that, in line with the theoretical foundations, the percentage of institutional ownership, board independence, and internal audit effectiveness have a significant and positive effect on performance. However, CEO duality leads to a decline in performance. Furthermore, earnings quality enhances the relationship between internal audit effectiveness and performance, and it also weakens the negative relationship between CEO duality and performance.