The main purpose of this research is to investigate the impact of tax avoidance on company performance, emphasizing the role of ownership structure. The current research is applied and from the methodological point of view, the correlation is causal type (post-event). The statistical population of the research is all the companies admitted to the Baghdad Stock Exchange and they were investigated in the period between 2017 and 2021. Also, to collect the required data and information, firstly, the library method and document studies were used. The basis, theoretical foundations and literature of the research were collected from specialized Latin books and magazines and explanatory notes of selected companies, compact discs of the image and statistical archive of the Baghdad Stock Exchange Organization. Then, the necessary data to test the research hypotheses were extracted by referring to the financial statements, the stock exchange website and other databases. In order to investigate the relationship between the variables, linear regression and Eviuz Naxe 8 software were used. The results of this research showed that the level of tax avoidance has a negativesitive and significant The effect on stock returns, as well as management ownership, has an inverse and significant relationship on the relationship between tax avoidance and stock returns, on the contrary, institutional ownership has no effect on the relationship of avoidance. There is no tax on stock returns.