An order management system automatically places an order with one of a plurality of suppliers when order information is input by one of a plurality of orderers. A terminal unit (A-N) is provided to each of the orderers. The terminal unit (A-N) is used for inputting the order information being transmitted to a central management unit via a communication network (6). The central management unit (7) manages order history information and section information with respect to each orderer. The central management unit (7) calculates a total cost of previous orderers based on the order history information of one of the orderers sending the order information and order information sent from one of the orderers. Execution of an ordering process is permitted when the calculated total cost of the previous orders is within a budget of the orderer.
