Purpose/Significance To explore the cognitive-affective-ability driving mechanism of users’ health digital hoarding behavior in social media, and to provide a basis for understanding the formation logic of this behavior and formulating intervention strategies. Method/Process Based on the risk information seeking and processing (RISP) model, the variables of fear of missing out (FoMO) are integrated, and a “cognitive-affective-ability” analytical framework is constructed. A total of 575 valid data are collected through questionnaire survey, and partial least squares structural equation modeling is used for empirical testing. Result/Conclusion Health risk perception affects health digital hoarding behavior through two chain paths:one is “health information anxietyinformation insufficiency”, and the other is “health information anxietyFoMO”. Perceived information gathering ability not only directly and positively affects this behavior, but also has an indirect effect by exacerbating FoMO.