The embodiment of the invention provides a purchase-sales integrated management system comprising the following parts: a supplier management module used for managing supplier information, product information provided by the suppliers, protocols between preset objects and suppliers, and evaluation information of the suppliers; a source searching module used for managing purchase demands, purchase projects, bid information, purchase review, contact, mechanism and finance payments of an enterprise, and making statistics and analysis for the purchase information; a material purchase module used for providing product display, product selection, order management, purchase approval, budget management, purchase progress query, trade merchant service and e-commerce service functions; a settlement module used for carrying out cost settlement and product cost collection; a supplier cooperation module used for shelving goods for supplier, receiving orders, delivering goods, receiving settlement bills and recording invoices; an e-commerce synergy module used for providing a sales function for e-commerce. The system can reduce the system operation cost.