Criteria for evaluating digital libraries have been suggested in prior studies, but limited research has been done to understand users' perceptions of evaluation criteria. This study investigates users' opinions of the importance of digital library evaluation criteria. Thirty user participants, including 10 faculty members and 20 students, were recruited from five universities across the United States. They were asked to rate the importance of evaluation criteria in eight dimensions (e.g. collections, information organization, context, etc.). The results demonstrate that users care about evaluation criteria related to the use and quality of collection and services rather than the operation of digital libraries. The findings of this study are relevant to the development of user-centered digital libraries and associated evaluation frameworks through the incorporation of unique users' needs and preferences.