In regard with the board characteristics, the results showed that board size did not influence the management of the operating components of the working capital. However, they improve the overall working capital management efficiency. When such boards are dominated by non-executive directors, they improve only the cash conversion cycle. Also, CEO duality doesn’t exert any influence on the efficient management of working capital components as well as the overall working capital measures except for the cash conversion efficiency. The intensity of the board meetings doesn’t improve the efficient management of the accounts receivable and the inventory. Further, in regard with the audit committee characteristics, the results show that larger audit committees improve both the accounts receivable management efficiency and the cash conversion efficiency but they don’t improve the accounts payable management efficiency. In addition, the independent audit committees improve only the accounts receivable management efficiency and the cash conversion cycle. Finally, the institutional ownership improves both the efficient management of the operating working capital components and the overall working capital management measures except for the inventory management and the operating working capital investment policy. From the foregoing analysis, it is evident that corporate governance mechanisms have significant impact on the working capital management efficiency.