Recently many domestic hospitals computerize and automatize the process to manage their own medical data. These medical data should be shared among the departments in the hospital and be held in common in case of patients transfers or references to the remote hospitals. However, there is no simple method to share data among the management systems to be shared due to their heterogeneous platforms. Schema sharing with systems and standard format data transfer could be a solution. In this paper, we propose HIES(Hospital Information Exchange System), which uses XML as a standard medical data transfer method. HIES uses XML, which is currently recognized as the standard of electronic documents, for integrating and managing heterogeneous and distributed medical data. Information Sharing Manager to maintain consistent schema information for heterogeneous database systems in hospital systems as well as Image Compression/Partition Manager for efficient image data transfer and reemergence among the systems are implemented.