Behçet's Syndrome (BS) is a chronic recurrent multisystemic inflammatory disorder characterized by oral and genital ulcers, ocular inflammation. Behçet's syndrome has a complex genetic etiology. However, epidemiological studies recommend that genetic factors have a significant influence to its pathogenesis, alike to other autoinflammatory disorders. Epidemiological statistics, clinical records and HLA typing were studied in Iranian Azari patients with Behçet's syndrome. This investigation considered HLA associations with BS and HLA with certain clinical characteristics, age and sex in the (Tabriz) Iran which has an ethnically homogeneous population. HLA-A and HLA-B typing was performed in 290 BS patients, conforming to International Study Group criteria and in 300 blood donors, as controls. Patient records were retrospectively reviewed and patients reassessed clinically. HLA-B5, HLA-B35, HLA-51, HLA-B52 and HLA-CW4 presented significantly high frequencies in all patients. No other HLA type was associated. There was a significant HLA link with male sex in BS patients and Mean age (34 +/- 1.1) was determined. We present the frequency and correlation between Iranian Azari patients with Behçet's syndrome and particular HLA antigens. Ninety nine percent had mouth ulceration, 64% genital ulceration, 72% skin lesions and 52% ocular involvement. This study supports HLA-B5, HLA-B35, HLA-51, HLA-B52 and HLA-CW4 immunogenetic predisposition in an ethnically homogeneous (Iranian Azari) population.