The invention relates to an integrated interface data transmission method of an E-commerce platform, a financial management and control system, an economic law business application system, and an SAP system. The provided platform includes an E-commerce platform, a financial management and control system, and an economic law business application system, wherein the present-stage integrated interface for the E-commerce platform, the main data platform, the SAP, financial management and control, and the business application related with economic law main includes synchronization of SAP contract number to E-commerce information, synchronization of SAP supplemental agreement generation information, execution of SAP order AOG (Arrival of Goods) information, execution of SAP order payment information, synchronization of SAP commissioning order questionnaire evaluation information, synchronization of SAP distribution receipt confirmation information, synchronization of SAP order generation information, synchronization of E-commerce contract validation identifier information, synchronization of E-commerce contract agreement information, synchronization of E-commerce difference chart information, synchronization of SAP contract and supplemental agreement information, synchronization of economic law contract validation information, and the above processes are associated. Through the business interface, business data exchange and business data sharing can be realized, and the practicality is high.