One of the challenges face corporate managers in the world is how working capital and growth opportunities influences capital structure of their companies. Show this problem for all company managers and other decision-makers in finance will be effective. The main purpose of this research is the assessment of the effect working capital and the growth opportunity on capital structure of accepted companies in Tehran Stock Exchange. In this research, the number of 107 companies in Tehran Stock Exchange has been examined during the period of 2009 until 2015. In order to test these hypotheses, we used Multiple-regression model for combined data. The results of research suggested that there was significant correlation between the financial leverage and sales growth rate, dividend growth rate, structural health ratio, debtor-sales ratio, liquidity ratio. In addition, no significant correlation between financial leverage and net income growth rate, inventory-sales ratio, cash-sales ratio, creditor-sales ratio, current asset-sales ratio.