Abstract: Objective Based on a large-sample health examination report,this study aimed to analyze the health examination indicator characteristics of extreme high altitude native populations (EHANP) in Tibet,so as to provide evidence for the assessment of health status and the formulation of public health strategies for indigenous populations residing at high altitude.Methods A retrospective analysis was conducted on health examination reports of EHANP who underwent health checkups at the Tibet Autonomous Region People's Hospital during November–December 2023 and September–October 2024,as well as high-altitude native populations (HANP) who underwent health checkups at the same hospital during February 2023.Routine blood parameters,liver and renal function indicators,blood pressure,and blood glucose were compared between the two groups.Results A total of 2699 EHANP and 7299 HANP meeting the inclusion and exclusion criteria were enrolled in this study.The results showed that EHANP had significantly lower red blood cell count,hematocrit,hemoglobin concentration,and mean corpuscular volume than HANP (all P < 0.05).Among female EHANP,red blood cell count,hematocrit,hemoglobin concentration,and mean corpuscular volume were all positively correlated with age (all P < 0.05),whereas no such correlation was observed between erythrocyte parameters and age in male EHANP.Platelet count and plateletcrit were negatively correlated with age in EHANP.In male EHANP,all liver function indicators except aspartate aminotransferase were higher than those in females (all P < 0.05).The proportions of abnormal liver function indicators in EHANP were higher than those in HANP across all age groups,and the proportions in both populations increased with advancing age.With the exception of female HANP aged 41–80 years,the proportions of abnormal renal function indicators in both EHANP and HANP generally showed an upward trend with age,with males exhibiting higher proportions than females.In EHANP,the proportions of hypoxemia and overweight were age-related and both increased with advancing age.The proportions of EHANP patients with hypertension,excessive erythrocytosis,chronic mountain sickness,and hypoxemia were all higher than those in HANP,and these proportions showed an increasing trend with age.Conclusion EHANP suffer from more severe hypoxic injury than HANP,with a cumulative effect observed as the duration of high-altitude exposure extends.Among them,middle-aged and elderly males exhibit a higher degree of hypoxic injury.The findings of this study provide a theoretical basis for the development of health promotion strategies for high-altitude residents.