SCM is one of the important key issues in Internet-based business environment. Most of companies related to B2B electronic commerce are making their efforts to innovate their existing business process into new integrated supply chain process. SCM system using XML/EDI provides competitive advantage to them by reshaping the relationship between traditional trading partners. This study intends to suggest a prototype of SCM system using XML/EDI. To implement SCM system, we analyze and design the supply chain process by using Unified Modeling Language, with a firm engaged in Korean automobile industry, which is a first vendor to produce a set of LAMP. The implementation of SCM system using UML shows excellent performance in software reuse, extensibility, and the interoperability with corporate internal information systems.