In order to determine the prevalence of hepatitis C virus (HCV) infection in the Black Sea region in Turkey, 287 serum samples taken from risk groups were investigated for anti-HCV antibodies using HCV EIA system. Anti-HCV antibodies were found to be positive in 51.2% of chronic haemodialysis patients, 20.6% of probable acute non-A, non-B hepatitis patients, 4% of patients who had multiple blood transfusions, 1.5% of the health personnel, while in new haemodialysis patients anti-HCV antibodies were not found.