As the Internet spreads rapidly, the industrial structure is changing to a new paradigm. The previous EDI system was asked to be changed and WEB EDI, E-Mail EDI, FTP EDI etc. based on the internet have appeared. Recently, the XML/EDI which is based on XML documents has appeared. EDI system has to assure a safe exchange between senders and receivers. But, the internet has security problems because it uses a open TCP/IP protocol. In this paper, we will propose an XML/EDI system with XML Signature.