Abstarct: Abstract The purpose of this study is to investigate the effect of outward foreign direct investment on the financial performance and value of companies listed on the Tehran Stock Exchange and OTC. 425 Tehran Stock Exchange and OTC companies as a sample were examined, Of these, 81 companies were foreign-invested companies. Combined data were analyzed by Eviews software. Return on assets is used as a measure of financial performance and three criteria of growth in the market value of the company, the Tobin's Q ratio and the percentage of changes in stock prices have been used to measure the value of the company. The results obtained from the least squares panel regression method show that outward foreign direct investment has a positive and significant effect on the financial performance of companies and a positive and significant effect on the value of the company baxsed on the criteria of growth of the company's market value and the Tobin's Q ratio, But it has no significant relationship with stock price returns.