The purpose of the paper is to measure impact of three determinants on the firm performance using the earnings quality as an intermediary variable. The three determinants measured in this research are firm specific return volatility, earnings management, and the corporate governance. The research is applied in the Egyptian stock exchange market, using the constituents of its most active index that is the EGX30 during the time frame 2010-2017. The data have been analyzed by using statistical techniques, like the Jarque-Bera Test, Pearson correlation, and structure equation modeling. The results of the statistical analysis approved the research hypotheses by proving the association among firms' specific return volatility, earnings management, corporate governance, on firms' stock performance in the Egyptian stock exchange market, using the earning quality as an intermediary variable.