Abstract: Under the background of the rapid development of "Internet+", the knowledge service work in university library has been facing new changes, new problems and new challenges, and presenting a new trend of development. Therefore, it is urgently need to speed up the transformation of service mode. Based on the connotation and main problems of knowledge service in university library, focusing on the new features and new requirements, this paper proposed six strategies of knowledge service for university library under the "Internet +" background: Reconstructing business management system, setting up humanized service concept, establishing cooperative service alliance, using the intelligent service, improving the service conditions of sharing and building the embedded service mode.