Objective To investigate the correlation between interleukin 1β gene-511C/T polymorphism of and essential hypertension in the Yi ethnic group of Yunnan province.Methods-511C/T polymorphism of interleukin 1β gene was detected by PCR-RFLP in 85 Yi patients with essential hypertension(EH group)and 106 Yi healthy people(control group)in Shuanghe Township,Jinning County,Yunnan Province.Genotype and allele frequencies were analyzed by SPSS 27.0 software,and association analysis was performed.Results The frequency distribution of CC,CT and TT genotypes at the mutation site 511 of the IL-1βgene in EH group was 18.82%,44.71%and 36.47%,respectively,and it was 5.66%,26.42%and 67.92%in the control group.The difference in genotype frequency between the two groups was statistically significant(P＜0.05).The allele frequency of C and T in EH group was 41.18%and 58.82%,respectively,and the allele frequency of C and T in control group was 18.87%and 81.13%.The frequency difference of alleles between the two groups was statistically significant(P＜0.05).Both genotype frequency and allele frequency found in males and females had statistical differences(P＜0.05).Conclusions The distribution of IL-1β gene-511C/T polymorphism is related to the incident of essential hyper-tension among the Yi ethnic group Yunnan Province,and is the susceptibility gene of the Yi ethnic group to essen-tial hypertension.