Ubiquitous business means to improve the business service and to create new business model under the environment which computing object is applied to real life and we can freely connect to network. As the related technology develops, the need of u-Business is rising in e-Business. Business formalities which are electronically processed through EDI or bar code, such as stock management, terminal gate management, container management, changes to the formalities using RFID. These formalities receive the sent input data through RDIF chip and antenna from RFID middleware, and transfer that data to server. In this paper, we propose the XML agent that transfers the input data to server and transfers the sent data from server to RFID middleware. The basic data form used at the proposed system is XML and the proposed system supports the converting functionality. The Converting functionality is to translate the received text to XML or XML to text. To provide the converting functionality, it is possible to migrate with various RFID antennas and middleware regardless of vendor. It also is able to migrate with the various information models as providing interface with server.