The intelligent service to be provided by the library is not simply to upload the information resources of the traditional library to the Internet, but to collect distributed digital resources with network access function, so as to realize the transformation from “flat” to “three-dimensional”. This paper combines virtual reality technology and student portrait algorithm to construct the management system of university library, and summarizes “library intelligent service” from three aspects: basic concepts, service characteristics and service subjects. Moreover, this paper takes resources, services, technology and librarians as the elements of library construction to realize the process of library intelligent service and management. Finally, through experimental research, this paper verifies that the model proposed in this paper has good effects and can effectively improve the management efficiency of university libraries.