Electronic patient records for radiation therapy (RT) consists of text, images and graphics. To enable the exchange of RT patient information between systems and institutions, a common standard is called for and the DICOM standard extension to radiation therapy is an appropriate means for standardization. This paper describes a model of DICOM-based electronic patient record system for information exchange and sharing. The system used a DICOM-based RT archive server as a common platform for archival of all RT related information including images and the web technology for distribution and viewing of the patient electronic record.