This article studies on a medical dictionary from Hong’s Diagnose and Secret Prescriptions with a Medical Dictionary (《洪家定診秘傳附醫書字 典》, <with A Medical Dictionary> for short, published in 1955). And a tentative research is made on these aspects, such as, the social history background of the book, the construction of the dictionary, the features of the dictionary, the selection of the Chinese characters and the explaination features the of characters, the meaning and value of the dictionary. This dictionary is high medical professional. And the characters has more paraphrases and the paraphrases have more correlationship with the medical. Thus, he dictionary has a big progress in the history of Korea Traditionary medical dictionary.

The research was completed on quantitative analysis to 92 rare Characters in a new-edition full medical dictionary. It shows there are two reasons which make a lot of rare Character come out from the appendix of the dictionary. One is not handling well the relations (simplified vs. traditional，variants，homophony) among characters. The other is insufficient corporation between computer science and related branch of learning, which makes the rare characters can’t be displayed and inputted. Good foundations of Philology will help distinct on relations among rare Characters. Fontlab software and MoveFileEx Windows API function etc can make characters display and unified update in the network environments.