SUMMARY
Working capital management means the balance between the current assets and liabilities, so that this balance can timely meet the needs of components of working capital management. In this study, the effect of working capital management is investigated on return on stock and profitability of elected glassmaking companies. So, four components, including collection period, inventory turnover period, accounts payable period and cash conversion cycle, are considered as the components of working capital management (independent variable) and their effects on return on stock and profitability (dependent variable) is investigated in forms of four questions. The statistical population of this study is composed of 5 glassmaking companies, including Glass and Gas, Mina glassmaking, Hamadan glass, Takestan glass and Razi glassmaking, that their data had been investigated during 2009 to 2013. The results show that collection period and accounts payable period have a significant effect on efficiency and profitability of the mentioned companies. And also, the inventory turnover and cash conversion cycle have a significant effect on returns on stock.