[Purpose/significance] To investigate the level and characteristics of online health information seeking be? havior of people with health anxiety, and to explore the influence of health anxiety on online health information seeking behavior.[Method/process] On January 30, 2021, solstice and February 22, 788 anonymous online questionnaires were distributed to Changsha residents through convenience sampling, and 699 valid questionnaires were obtained by collecting user information using somatic symptom severity scale (PHQ-15), OHIB scale, Intolerable Uncertain Scale (IUS) and health anxiety scale (SHAI).The recovery rate was 88.7%.[Result/conclusion] In this study, ①The SHAI points.②There was a positive correlation between OHIB score and total HA score, likelihood of disease and negative outcome score (r=0.117-0.184, P<0.05).③Health anxiety inseeking behavior (search scenario, motivation, frequency, search information types, disease types, platform) there are significant differences (P＜0.05). ④IU played a mediating role between health anxiety and online health information seeking behavior.Conclusions: ①Different levels of health anxiety have different search behavior preferences. The higher the level of health anxiety, the higher the frequency and duration of online search. ②Health anxiety has a causal relationship with search behavior and can be used as a predic? tor of search behavior. ③Health anxiety affects search behavior through the inability to tolerate uncertainty, and search behavior can be optimized by alleviating health anxiety and the degree of uncertainty tolerance.