Investigating the Effect of Corporate Governance on the Financial Performance of Companies in Tehran Stock Exchange

"Separation of control from ownership of a company is "a response to the question of the agency or agencies that is due to "the system of corporate governance "Objective of This, is to study, examine relationship between corporate governance mechanisms involve: percent of non-executive directors on board, block holder ownership, institutional ownership and ownership concentration on operating financial. consisted of 114 companies listed in Tehran stock exchange during 2005-2011, which were selected by screening hypotheses tested by multiple regression and generalized least squares method (GLS) was performed. The result corroborate that there is a significant relationship between the percent of board, and there is indirect relation between the block holder ownership, institutional ownership and ownership concentration with operating financial