【Purpose/significance】 Identifying the key influencing factors of social media users' health information avoidance behav⁃

iors from the perspective of risk perception, in order to effectively improve personal health management and decision making, and to provide a reference for social media operation management and sustainable development.【Method/process】 Based on the Risk Infor⁃mation Seeking and Processing (RISP) model, an index system of influencing factors of social media users' health information avoid⁃ance behaviors is constructed from six dimensions: perceived risk characteristics, relevant channel beliefs, negative emotional re⁃sponses, information sufficiency, information avoidance norms and perceptual information gathering ability. The factor relationship net⁃work diagram is constructed by the triangular fuzzy DEMATEL method, and the weights of key influencing factors are quantified with the help of DANP method.【Result/conclusion】 Based on the limit super matrix, reason degree and centrality ranking results of influ⁃encing factors, the key influencing factors of social media users' health information avoidance behaviors, such as accessibility, per⁃ceived severity, high arousal emotion, and existing information level are identified and corresponding optimization strategies were pro⁃posed.【Innovation/limitation】 Based on the perspective of risk perception, this study reveals the key influencing factors of social me⁃dia users' health information avoidance behavior, which has certain guiding significance for promoting the operation management and sustainable development of social media. However, the quantitative index is relatively subjective, and the sample data needs to be fur⁃ther enriched and improved.