This study aims to evaluate the usability for improving quality of Hoseo university digital library website. Compatibility of web browser and loading speed are analyzed in using Doctor HTML and Web Site Garage, and seven major attributes of website. that is navigation, functionality, user control language and contents. system and user feedback, consistency, architectural and visual clarify, are analyzed and evaluated in using online questionnaire method. Finally this paper was suggested some problems and improvements of that website mentioned above, and general guidelines of website construction based on usability in university digital library in korea.