The development of virtual reality brings about opportunities and challenges for the library. The actively practices of libraries domestic and overseas provide successful use for reference for the application of virtual reality. The article summarizes the applications of virtual reality in the library, and then selective analyzes the role definition and innovative service of library base on virtual reality. Finally, it considers the roles of library in the virtual reality includes: offer and operator of experience facility; transformer of basic services; cultivator of innovative thinking. Meanwhile, it also considers VR technology driving the innovative services of the library, such as resource management and retrieve, space navigation and wandering, VR reading, virtual consultation and other individuation services.