Abstract: The establishment of user model, based on the user＇s interests and hobby, is the key techniques in the individuation-service- system in digital library. Based on the general individuation-service and user-model in digital library, the paper discusses the expressive method, the source of information and the technical types of the user-model in digital library.

Key words: Digital Library, Individuation Service, User Model, User Interest, Vector Space Model, Interest Granularity