Predicting stock return rates and securities pricing is one of the most important issues in financial markets. The information provided by managers in corporate financial statements helps investors make optimal decisions. The value of this information depends on its accuracy and correctness, and managers' biases distort the information and lead to incorrect predictions and, in turn, wrong decisions. Corporate governance is created by overseeing the opportunistic behaviors of managers and with the aim of reducing the conflict of interest between shareholders and managers. The aim of this study is to investigate the effect of corporate governance mechanisms on the relationship between managers' expectations and stock returns. Stock returns were calculated using the Fama and French three-factor model. It is an institutional agent and shareholder. The research hypotheses were tested using data from 178 companies whose data were available during the years 1390 to 1396 and using multivariate regression and combined data. Findings indicate that there is a significant relationship between managers 'expectations stickiness and stock returns. Also, only the mechanism of the percentage of institutional shareholders has a significant effect on the relationship between managers' expectations stickiness and stock returns.