To estimate the seroprevalence of HCV infection among HIV-infected haemophiliacs and to demonstrate the most prevalent HCV genotype, 47 HIV-infected haemophilia patients were screened for anti-HCV antibodies. By performing polymerase chain reaction and DNA enzyme immunoassay, HCV-RNA was detected with subsequent genotyping. Seroprevalence of anti-HCV antibodies was 66.0%. Of 31 HCV/HIV co-infected patients, 21 (67.7%) had no history of blood transfusion. We detected 4 HCV genotypes: 1a, 1b, 4 and 4 mixed with 3a, HCV-1b being the most frequent. Contaminated factor VIII (clotting factor) could be responsible for disease acquisition.