Competition in the product market by reducing the efficiency of managers, increasing transparency in decision-making, improving the level of accountability of managers, reducing the risk of incorrect investment decisions and realizing prices in the market can reduce representation problems and information asymmetry between managers and stakeholders. This factor reduces the risk of falling stock prices. The purpose of this study is to evaluate the relationship between overtaking in the commodity market and the risk of stock devaluation in companies listed on the Tehran Stock Exchange. The statistical population of the present study is the companies listed on the Tehran Stock Exchange, which was selected as a statistical sample by the method of systematic elimination of 112 companies in the period 1392 to 1397. Logistic regression method has been used to test the hypotheses of this research. The findings of this study showed that there is a significant relationship between competition in the product market and stock price risk. To prove this hypothesis, Herfindahl-Hirschman index and Lerner index were adjusted Lerner index and all direct and significant relationship between competition in product market and Proved stock price risk. That is, as the Herfindahl-Hirschman index rises and the Lerner index rises, so does the risk of a stock falling. The results of this research can pave the way for capital market activists and other investors.