【Purpose/significance】Public attitudes and reactions to public libraries on social media platforms can reveal the character⁃

istics and patterns of information demand of the public. This study aims to build an optimal strategy for public library information ser⁃vices in the post-epidemic period.【Method/process】Sina Weibo is used as an example, and public Sina Weibo data is used as the re⁃search object. Firstly, the microblogging public opinion is divided into stages. Secondly, the information demand themes of public are mined from Sina text data through the LDA2vec theme model. Then, the characteristics and intensity of public information demand at different stages are revealed from the demand theme and time dimensions, and their temporal evolution patterns are explored. Finally,based on the public information demand, a strategy for information services in public libraries in the post-epidemic era is proposed.【Result/conclusion】The information demand of public in the post-epidemic period revolve around four main areas: environment,thoughts, emotions and behaviours, and suggestions are made for the future information services of public libraries from these four ar⁃eas.【Innovation/limitation】By analyzing the public's demand for public library information and the law of time evolution, the public li⁃brary information service strategy is constructed. Future research demand to expand the research sample to make the research conclu⁃sion more general.