Abstract: 【Purpose/significance】By building an online health knowledge co-creation model from the perspective of Internet dialogue,
the mechanism of online health knowledge co-creation is revealed, so as to provide countermeasures for promoting online health
knowledge co-creation on mainstream social platforms【. Method/process】Firstly, build a theoretical framework of online health knowl? edge co-creation model by integrating dialogue theory and group discussion theory together. Secondly, based on the online dialogue text of "cervical cancer" topic on Zhihu platform, including 152 questions and 30245 replies, the proposed theoretical framework is tested, content analysis and text analysis are used to explore the dialogue cycle mechanism and dialogue intervention mechanism in the co-creation of health knowledge, and the linear regression analysis is used to reveal the impact and difference of dialogue interven? tion activities on the co-creation effect of health knowledge【. Result/conclusion】The online health knowledge co-creation model based on dialogue theory consists of two modules: co-creation based on dialogue cycle and co-creation based on dialogue intervention. The dialogue cycle follows the discussion logic of "from topic to plan", and relies on the interactive function of the online communication platform to realize the coherence of multiple dialogues spaces. Dialogue intervention emphasizes the linguistic function of online text, and is subdivided into dialogue expansion and dialogue contraction, both of which affect the health knowledge co-creation effect in a single dialogue space.【Innovation/limitation】Based on dialogue theory, construct an online health knowledge co-creation model and reveal the influence of dialogue factors on the effect of knowledge co-creation. However, only the health dialogue data of the Zhihu platform is used for testing, and follow-up research must introduce the health dialogue data of various types of online platforms for model verification and optimization.