Abstarct: Abstract The purpose of this research is to analyze the role of risk and behavioral factors on deviations in the valuation of shares of companies listed on the Tehran Stock Exchange. This research is practical in terms of purpose and causal in terms of nature and method. Also, in terms of the time of occurrence and the type of data, then it is an event baxsed on objective and real data. The statistical sample of this research includes 146 companies admitted to the Tehran Stock Exchange in the period of 1390-1400, and Excel and Eviews software were used for data classification, processing and analysis. In order to check and test the hypotheses, quantitative regression tests and test equality model have been used. The results obtained from the tests show that the ratio of book value to market value, which is a component of behavioral factors, has a significant effect on pricing error, but this effect is not symmetrical. This means that in the quantile regression test it has a positive effect and in the slope equality test it has a negative effect on the pricing error. Also, all the risk components, which include systematic, unsystematic and bankruptcy risk, affect the stock pricing error of listed companies. According to the results of this research, all research hypotheses were confirmed.