HLA class I and II antigens are common among patients with ulcerative colitis. They can be involved in the autoaggressive mechanisms of the disease. The aim of the study was to evaluate the prevalence of HLA B and HLA DR antigens and estimate the correlation to extra-bowel manifestations of the disease. 50 patients with ulcerative colitis and 20 healthy controls were examined. HLA-B27, -B7, -B40, -DR1, -DR2, -DR3, -DR4 and -DR7 were determined using monoclonal antibodies in microlymphocytotoxic method. HLA I and/or HLA II antigens were detected in 36% of patients: HLA I in 28% and HLA II 16%. 46% of the patients were demonstrating joint changes, with 65% of them presenting HLA molecules. 16% of the examined patients presented symptoms of intrahepatic cholestasis; with 67% having HLA I/II molecules. The difference from the control group was statistically significant, only 25% of healthy persons presented HLA I/II antigens. The incidence of joint involvement and cholestasis was higher in ulcerative colitis patients with HLA class I and/or HLA II.