As changed the clinical environment, the interest on u-Healthcare service and systems has been increased. The ubiquitous healthcare(u-Healthcare) systems are constructed at the integrated environment that consists of various devices and systems basically such as personal health devices(PHDs) measuring body signals, information aggregators gathering the data transmitted from PHDs through wireless technology, and health information systems storing and managing personal health information transmitted from the information aggregators. International standards such as IEEE 11073 and HL7 have been specified for the interoperability of PHDs and health information systems, but the research on u-Healthcare systems that were developed and applied in the real clinical environment by adopting the standards was rarely conducted. Therefore, we developed an u-Healthcare system which can manage personal health information, such as blood glucose, blood pressure, and body composition, based on health information exchange standards. Moreover, we verified the stability of the developed system through clinical trial in patients with endocrine disease at the Kyungpook National University Hospital, and listed problems occurred during clinical trial and found their solutions.