The goal of the Korean Medical Health IC card is to fully incorporate with a hospital information system (HIS) in various medical institutes and also to cooperate with other EDI and HIS systems maintained by the Korean government and other medical institutes. Proposed system is built on Client/Server computing environment. The server is currently being developed to run under the Windows NT environment. In near future, the server will be expanded to UNIX environment which is widely used in the larger medical institutes. The proposed system facilitates functions to secure medical information using Crypto-API which is the basic security mechanism provided in the Windows NT system to construct a system environment together with the operating system. This paper focuses on the following three categories: 1) Review on up-to-dated status of IC card technology issued in international and domestic area and medical informatics, 2) Research on the development of Korean standardization of medical information stored in the medical health IC card and relations with existing/planned international standards, and 3) research on the current status of existing medical databases adopted in Korean medical institutes. The key issue of a medical health IC card is to incorporate IC card into a client system as a PC system-following the PC/SC guidelines that tightly coupled between the PC system and the IC card subsystem. The owner of the medical health IC card can bows his/her medical information using a client application, which is developed to access the medical information and the IC card terminal. The owner also can request other extra medical information on the medical institutes' database through the network information retrieval system. The Korean Medical Health IC card enhances the interface usability so that user can easily use a medical health IC card in a general network environment such as an electric commerce system. As a part of our long term plans, to cooperate with the existing EDI and HIS systems developed on domestic medical institutes and related government institutes, the investigation and analysis of domestic medical system is being under way. The developed system will also be put into field tests in major domestic hospitals and the Korean medical insurance management institute.