隨著外在服務環境的變遷以及內部專業人力及經費之不足，大學圖書館為支援教學與研究所提供之參考服務在品質上逐漸遭受質疑，引發了學界及業界對資訊時代參考服務之重新省思。有鑑於此，本文首先對傳統參考服務之特色及優缺點加以探討，並介紹學者所提倡之「分化式參考服務模式」（Differentiated Reference Service Model），就其產生之背景、觀念之演進、服務之特色、及實施之優缺點詳加論述，並由美國幾所大學圖書館 施之現況分析其實際應用之可行性。結論指出，分化式參考服務模式對參考服務品質之提升確有有助益，相當具有可行性，可作為資訊時代大學圖書館參考服務組織重整時之參考。

　　　　　Three trends have pushed university libraries to modify the structure of reference service in recent years, which are budgetary stringency, reduuctions in staffing, and the change of reference environment. University libraries can not but change the reference model in order to satisfy readers' needs in informaton age. This article explores the problems of traditional reference service, introduces the differentiated reference model, including its background, progress, characteristics, advantages and disadvantages, and analyzes the feasibility of the model by the experience of serveral university libraries in the United Sates.