Corporate governance has been raised as one of the most important issues among the international business environment since the beginning of the twenty-first century. At first, corporate governance basic principles focused on firm’s strategies and the rights of their shareholders but these principles has been changed into the rights of all stakeholders and society through researchers new viewpoints. Although corporate governance codes and regulations are different in various countries, there is a common unanimity that better compliance of corporate governance improves financial reporting quality and transparency. The aim of this paper is to investigate the impact of corporate governance mechanisms on financial reporting transparency in Tehran Stock Exchange over a seven year period (from 2006 to 2012). Besides we have specially reviewed related researches and topics about corporate governance in various countries which their results were discussed in different parts of the article. In order to examine the hypothesis a sample of 67 companies is used. In this paper we used ownership concentration, institutional ownership, board independence, board size, CEO duality and CEO tenure as the corporate governance mechanisms. We also used earnings management behavior by employing Kasznik model (the absolute value of abnormal accruals) as a measure of financial reporting transparency. To test research hypothesis a multiple regression with estimated generalized least square method is employed. The findings indicate that ownership concentration, institutional ownership, board independence and CEO tenure has positively affected financial reporting transparency through earnings management behavior. On the other hand board size and CEO duality has negatively affected financial reporting transparency through earnings management behavior.