[目的/意义]老年病年轻化趋势日益显著，为应对由此引发的青年健康信息焦虑问题，需深入剖析其成因。[方法/过程]基于健康信念模型和MOA理论，提出12个研究假设，构建青年群体健康信息焦虑形成机理模型。通过问卷调查收集401份有效数据，使用AMOS软件进行数据分析并检验青年群体健康信息焦虑形成机理模型。[结果/结论]感知易感性显著正向影响青年健康信息焦虑，而自我效能则呈现显著的负向影响；感知严重性和感知障碍与青年健康信息焦虑无直接关联。感知易感性在健康状况和青年健康信息焦虑的关系中存在完全中介效应，自我效能在健康信息质量、健康信息异化与青年健康信息焦虑的两条并行路径中均发挥完全中介效应。此外，自我效能在健康信息素养与青年健康信息焦虑的关系中起部分中介作用。

[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.