To provide more ways for users to freely access to information and collections from Peking University Library (PKUL), PKUL constructs an information system to provide mobile services. Firstly, PKUL investigates and evaluates the status of mobile service, users’ requirements and mobile devices of Peking University. Based on Wireless Application Protocol(WAP), the system has been designed and developed on three fields of emergency service, interactive service and personalized service. With the fast development of mobile terminator technology in short time, traditional desktop information systems provide more and more mobile service. With the improvement of behaviors and habits of users, PKUL mobile services will adopt a unified APPs with more independences, more integrations and more innovations compared with the existing system based on WAP in the near future.