This study tests the efficient structure hypothesis and the role of human capital efficiency in predicted relations in this hypothesis as well as the quiet life hypothesis and the role of management optimism in predicted relations in this hypothesis. For this purpose, the data from 136 companies listed in Tehran Stock Exchange during 2010 to 2014, linear regression, and panel data models were used. The results showed that an increase in industry concentration, and in other words, a decrease in industry competition, will improve firm’s efficiency index (disapproving the quiet life hypothesis in Iran’s Capital Market) and increasing human capital efficiency, in addition to enhancing the direct relationship between industry concentration and firm’s efficiency, improves firm’s efficiency (confirming the role of human capital efficiency in the relationship between industry competition and firm’s efficiency). Moreover, the firm’s efficiency will increase firm’s growth (confirming efficient structure hypothesis in Iran’s Capital Market) and management optimism, in addition to increasing firm’s growth, would enhance the direct relationship between efficiency and firm’s growth (confirming the role of management optimism in efficient structure hypothesis).