Abstract: 【Purpose/significance】The study aims to reveal the distribution characteristics of the health and wellness information needs of users on social platforms and explore the motivations and evolution trend of needs【. Method/process】Taking the posts in Zhihu,a typ⁃ical social Q&A site in China as research objects,this paper used LDA and BiLSTM models for topic extraction and sentiment analysis.Then,dividing the time series,the evolution of topic attention was analyzed by Maslow's hierarchy of needs theory.The results found that in terms of demand content,users' health and wellness information needs covered 20 topics.【Result/conclusion】Compared with the traditional health information needs that focus on diseases,the health information needs were more diverse in content and had high⁃er needs levels.On the evolution of the concern of demand,safety demand and respect demand become hot spots,and the new crown epi⁃demic strengthens users' concern about the demand of health and wellness information.In terms of the intrinsic connection between topics,users' attention to the topic of respect needs is transferred to the topic of security needs in the form of "commoditization"【. Inno⁃vation/limitation】This paper focuses on the health and wellness information needs for the first time,and explores the changing trends of users' health and wellness information needs in a fine-grained way through topic and evolution analysis.In addition,the data source of this paper comes from the same platform,and subsequent research can analyze the health and wellness information needs of multi-plat⁃form users and deepen the motivation.