The effect of corporate governance mechanisms on Tax avoidance in Tehran Stock Exchange listed companies

Purpose of this research is examination of some corporate governance's mechanism( board of director Independence, board of director size, board of director financial expertise, institutional investors and, CEO duality and government ownership ) effects on Tax Avoidance in Tehran Stock Exchange listed companies.To achieving research purpose, 83 firm during 5year from 2007 to 2011 is stuied and A Model used in which corporate governance mechanism(board of director Independence, board of director size, board of director financial expertise, institutional investors and, CEO duality and government ownership) as a independent variable, Tax Avoidance as a dependent variable provided. Excel spread sheet for variable calucation and SPSS for Analyse and estimate models and hypothesis Test is used.Finding show that board of director Independence, board of director size, institutional investors andgovernment ownership can have signficiant effect on Tax avoidance level in the Tehran stock exchange listed companies. Also, Overall findings show that with increase some corporate governance mechanisms, the Tax avoidance level is decreased