[Purpose/significance] The trend of age-related diseases manifesting at younger ages is becoming increasingly prominent. To address the issue of health information anxiety among young groups resulting from this trend, it is essential to investigate its underlying mechanisms. [Method/process] Drawing on the health belief model and the MOA (Motivation-Opportunity-Ability) theory, this study proposed 12 research hypotheses and constructed a model of the formation mechanism of health information anxiety among young groups. It then distributed a questionnaire survey,which yielded 401 valid responses. Finally, the study utilized AMOS software for data analysis and model testing. [Result/conclusion] Perceived susceptibility has a significant positive effect on health information anxiety among young groups, while self-efficacy exhibits a significant negative effect. In contrast, perceived severity and perceived barriers are not directly associated with health information anxiety. Perceived susceptibility fully mediates the relationship between health status and health information anxiety. Self- efficacy fully mediates the two parallel pathways linking health information quality and health information alienation to health information anxiety. Additionally, self-efficacy partially mediates the relationship between health information literacy and health information anxiety.