The purpose of this study was to investigate the effect of air pollution and environmental factors on financial performance. Spatial realm, companies listed on the Tehran Stock Exchange and realm of time, from 2014 to 2018. In this study, air pollution and environmental factors were considered as independent variables and the financial performance of listed and OTC companies was considered as a dependent variable. The present study is in the category of applied research and in terms of nature is in the category of descriptive research and in terms of method is in the category of correlational research. In the research data section, data collection of sample companies was performed by referring to financial statements and explanatory notes. Based on the systematic elimination method, 135 companies were selected as a statistical sample. In order to analyze the data, first F-Limer F-tests, Hausman test and Jark-Bra test were used and then multivariate regression test was used to confirm or reject the research hypotheses (Eviews software). The results showed that the effect of air pollution and environmental factors on financial performance including equity returns, stock returns, financial risk and changes in financial risk in listed companies is different from OTC companies. The results can increase the understanding and knowledge of investors and researchers in the field of capital market and in the light of it can identify other factors that have the ability to explain changes in financial performance. The results of the research are in line with theoretical foundations and can help managers in proper management and shareholders in investing and determining company policies and procedures.