Abstract: 【Purpose/significance】Explore the social and knowledge sharing behavior characteristics of opinion leaders in the online question-and-answer community, so as to provide improvement suggestions for its development.【Method/process】Taking active us⁃ ers under the topic of“travel”Q&A as the research object, crawling the user’s personal information through python, using mathemati⁃ cal statistics and social network analysis to study the social and knowledge sharing behavior characteristics of opinion leaders.【Result/ conclusion】The study found that social characteristics are the prerequisites for opinion leaders to carry out knowledge sharing activi⁃ ties. The development of online Q&A communities is inseparable from the diversity of community users; opinion leaders generate the main force for Q&A community content, and knowledge sharing behaviors are widely distributed in opinion leaders' information activi⁃ ties and their behavioral influence are outstanding; the central group jointly promotes knowledge sharing among opinion leaders, and knowledge sharing and interaction among leaders’groups are frequent.【Innovation/limitation】The analysis of the characteristics of opinion leaders is only based on the question-and-answer topic of "travel", and the number of samples is low. In the future, more ques⁃ tions and answers will be studied in order to draw more accurate and more universal conclusions.