Objective To explore the relationship between IL26 gene polymorphism and the susceptibility and severity of tuberculosis in Han Chinese. Methods A case-control study was undertaken, wherei n 1137 tuberculosis patients treated in the inpatient wards of West China Hospital, Sichuan University from January 2013 to December 2020 were designated as the case group. This group comprised 579 cases of mild tuberculosis and 558 cases of severe tuberculosis. For comparison purposes, a control group of 581 healthy individuals undergoing physical examinations was selected. Both groups underwent peripheral blood DNA extraction and IL26 gene typing. Results No statistical differences were observed in the age and gender composition between the case group and the healthy control group. The frequency distribution of the three Tag SNPs sites (rs3741809, rs10784693, rs741344) within the IL26 gene, as well as the genetic model analysis (encompassing allele model, additive model, codominant model, recessive model), revealed no significant statistical variance between either the tuberculosis group or the healthy control group. Similarly, no significant differences were found between the mild tuberculosis group and the severe tuberculosis group (P＞0.05). These findings remained consistent both before and after adjusting for age and gender variables. Conclusion No significant correlation is observed among the three Tag SNPs sites of the IL26 gene (rs3741809, rs10784693, and rs741344) and the susceptibility or severity of tuberculosis in Chinese Han population