The paid knowledge live of the social Q&A community provides users with a way to interact with content creators online. How users measure the quality of information and finally adopt the paid information has high research value. Research on users' adoption of knowledge payment is conductive to open new knowledge-paying user market. This article takes Zhihu Live as the research object, builds a theoretical framework through the information adoption model, and explores the influencing factors of users' payment information adoption behavior. We combine text analysis method to perform regression analysis on characteristic data to verify the theoretical model. The research results show that carrier richness, content live broadcast duration and content professionalism will significantly affect information quality, while content interestingness has a negative impact. Information quality and credibility of information sources will positively and significantly affect the users’ final adoption decisions, while information acquisition costs will have a negative impact.