This study aims to designed and implemented a prescription support system to search and suggest prescriptions to treat symptoms of patients based on Korean medicine ontology. The Korean medicine ontology have constructed to represent the information on textbooks used in Korean medicine colleges using Web Ontology Language (OWL). However, OWL is stored and queried in the form of a graph database. Because it is not flexible to link with other systems such as electronic charts, we convert the graph data of the OWL database to the table data of the relational database. We also designed the database tables for the prescription support system based on the e-government framework. The prescription support system in this paper constructed to provide the functions such as prescription search, patient management, and treatment management to facilitate the practical clinical uses. The user interface was designed for the convenience of inputting symptoms, and functions of the prescription management such as sort, comparison, addition and subtraction, and agreed prescription were implemented. In the future, we will study to increase the utilization of the prescription support system in connection with electronic charts in hospitals and mobile applications for the personal health care. In addition, the prescription recommendation function will be enhanced by using the classification and synonyms of symptom terms.