This study examines the relationship between corporate governance’s mechanisms and liquidity of stocks on 66 selected firms listed on Tehran Stock Exchange over the period 2005-2009. Board composition and ownership structure are used as corporate governance’s mechanisms and illiquidity measure proposed by Amihud (2002) [Amihud, Y. (2002). Illiquidity and stock returns: cross-section and time-series effects. Journal of financial markets, 5(1), 31-56.] is used to measure stock liquidity. The results show that an increase on the number of independent boards is associated with higher liquidity. In addition, the results show that there was a significant relationship between liquidity and ownership structure. In other words, the relationships between liquidity and individual investors and five biggest investors are positive and the relationships between liquidity and institutional ownership and the biggest investor ownership are negative. In addition, there is not a significant relationship between liquidity and duality of managers.

In the present study, the separate and simultaneous role of concentration and type of ownership on corporate value is investigated. In this study, the ownership structure is classi?ed into four classes: the institutional ownership, the corporate ownership, the management ownership and the foreign ownership. In addition, di?erent attitudes regarding the above ownership are also tested, that is, active monitoring hypothesis and interest convergence hypothesis. Since, in the sample research no information was found about foreign ownership, this type of ownership was not examined. However, in the case of the other ownerships, a separated hypothesis was developed based on various techniques and their in?uence on the corporate value was examined. For each hypothesis, a multiple linear regression model is de?ned based on the dependent variables. Companies listed in securities exchange commission of Iran makes up the statistical community of present study and the sample consists of 90 companies during 2002-2008. Two types of tests, including correlation test and cross multiple regression test are implemented to examine the hypothesis. Generally, the results reflect no signi?cant relationship between the concentration of ownership and the corporate value. The results of the study show that, while there is no relationship between the institutional ownership and management ownership and the corporate value, there is a signi?cant relationship between the corporate ownership and the corporate value.