In this study, the effect of timely quarterly financial statements on stock liquidity was reviewed in the listed companies of Tehran Stock Exchange. The stock liquidity of 51 listed companies during the period after timely quarterly unaudited statements was examined over the years 2008-2011 in the Stock Exchange. In order to measure stock liquidity as a dependent variable three proxies were used, including bid-ask spread, average of price depth and stock turnover. At the first step, Willcoxson test was used to test the research hypotheses, comparing the variable means and then to reexamine the results. The regression analysis was also employed. The results showed that the timely disclosure of interim financial unaudited statements had a significant effect on the bid-ask spread but the effects on other dimensions such as price depth and stock turnover were insignificant.