Generally, because individual agricultural product possesses its own distinctive characteristics and shows different characteristics at each stage of the agricultural supply chain, it is necessary to develop a proper enterprise architecture for managing information system. In this paper, we propose an enterprise architecture based on RFID/USN technology that can be used as a reference enterprise architecture for u-IT application in the agriculture sectors, which is called the u-Farm enterprise architecture with taking heterogeneous characteristics of agricultural products into account for. In addition, we also developed the RFID/USN middleware platform as a core infrastructure technology. Fo evaluation of the performance of the proposed u-Farm architecture and the RFID/USN middleware platform, the field-trial evaluation at the apple Agricultural Processing Center (APC) has been executed and the results shows that the proposed architecture and platform perform well in terms of information integration over the whole SCM process from the farming stage to delivering statge to the customers. It is expected that the proposed u-Farm enterprise architecture can be utilized as a standard information architecture, and the RFID/USN middleware platform can be a infrastructure platform for future u-IT based information technology applications and services in the agricultural environment.