[Purpose/significance] This paper establishes a set of specific service model for WeChat-based subject service for the current situation, and guides the libraries to provide readers with a convenient subject service.[Method/process] According to the meaning of subject service and the function modules of WeChat, the paper analyzes the feasibility of WeChat applied to subject service. Through the research on WeChat public platform of university library of 211 Project, this paper describes the current situation of the use of WeChat to carry out subject services in university libraries.[Result/conclusion] The results show that, it is suitable that WeChat public platform be used for subject service as a carrier. But at the same time, only a handful of university libraries have tried in this regard; and the existing WeChat public platform is used as a platform for information release, rather than the provision of services; and the service provided by WeChat public platform focuses on forms rather than contents. And then, this paper presents the ways to carry out subject service base on WeChat public platform, including information push, interact, form processing, online courses and study groups, etc. Finally, this paper points out some problems that need attention, including how to promote the platform,which type of platform to choose, and how to ensure the reader viscous and trust degree, etc.