Abstract:  Class I human leucocyte antigen (HLA)‐B51 is well known to be associated with Behcet's disease in many ethnic groups. However, there has been no published paper with respect to its association with HLA class I and class II among the Turkish people who live in the eastern region of Turkey. Moreover, as it is known that B51 antigen is encoded by 21 alleles, B*5101–5121, HLA‐B51 allele typing was performed, as well as HLA class I and class II genotyping of 75 patients with the disease and the 54 individuals in the matched control group. The result shows that the HLA‐B51 frequency was significantly higher (58.66%) in the patient group, compared to that in the control group (18.51%) (OR = 6.245). In the subtyping of B51 alleles, 44 B51‐positive patients possessed B*5101 (45.5%), B*5108 (25%), B*5105 (9.1%) and B*5104 (4.5%). There was no significant difference in the HLA‐B51 allelic distribution between the patient group and the control group. However, homozygous carriers of HLA‐B51 showed considerably high risk (OR = 2.647) in the patient group, compared to that in the control group. In the genotyping of class II HLA alleles, while HLA‐DRB1*04 (45.3%) and HLA‐DRB1*07 (24%) were the predominant alleles in the patient group, DRB1*11 (50%) appeared to be more common in the control group.