Finance and economics literature includes many attempts to determine the factors influential on working capital and working capital management. The present study aims to find out the relationships between working capital and macroeconomic variables. To this end, 11-year financial statement data of 128 companies traded at Borsa Istanbul from the 2003 to 2013 period were examined, and artificial neural network modeling was administered to the data obtained from these financial statements. The level of working capital, return on working capital, and cash conversion cycle were used as dependent variables and analyzed separately. Macroeconomic variables such as inflation, export index, import index, foreign exchange rate, interest rate, stock market index, gross domestic product, and gold prices were used as independent variables. The research findings show that there are relationships between working capital and macroeconomic variables; working capital is influenced by macroeconomic variables; the level of working capital is influenced most by export index and stock market index; return on working capital is influenced most by import index and stock market index; and cash conversion cycle, which represents working capital management, is influenced most by benchmark interest rate, gold prices, and foreign exchange rate.