Recently, Technical innovation has been implemented in a broad variety of industry fields to reach an ubiquitous society, with the object of popularizing u-Hospital, the mobile technology with no restriction to the place tends to be used positively in Health care fields. The existing mobile medical reservation system has the problem of not making good use of location information of users due to the interface based on text in the existing web pages. This paper proposes an mobile medical reservation system using geographic information service to solve the problems of current reservation system by using RIA(Rich Internet Application) technology applicable to Web 2.0 environment. Our proposed system also does the all required processes in a few page view, gets the differentiated service from the existing system by allowing efficient data exchange using XML, and expects the improvement of user friendliness by flexible user interface.