Financial information transparency has always been one of the most effective variables in determining investment strategy in financial markets. However, managers as the authorities to prepare financial statements always have had the incentive to deviate financial information to preserve their own benefits. Also earnings opacity has been one of the effective factors in investors' behavior. Accordingly, when negative news is accumulated within a company and the earnings of an economic unit has lots of fluctuations, stock price suddenly crashes. Therefore, the present research is going to study about the effect of variability and opacity of earnings on stock price crash risk in firms enlisted in Tehran Stock Exchange. In this research 124 firms were investigated during the time period between 2008 and 2012. To test hypotheses we have used logistic regression model. Research findings showed that earnings opacity and earnings variability have had a positive and meaningful effect on stock price crash risk.