To investigate the positive rates of antibodies to hepatitis C virus (anti-HCV) in Chinese cirrhotic patients with or without hepatocellular carcinoma and to evaluate the influence of blood transfusion on the prevalence of anti-HCV in such patients, a longitudinal study in 30 cirrhotic patients (17 combined with hepatocellular carcinoma) was carried out. Five patients (16.7%) were anti-HCV positive before transfusion. The positive rate of anti-HCV in HBsAg-positive patients and HBsAg-negative patients was 9.5% (2/21) and 33.3% (3/9), respectively. The positive rates in cirrhotic patients with or without hepatocellular carcinoma were 23.5% (4/17) and 7.7% (1/13), respectively. The positive rate of anti-HCV increased significantly after multitransfusion, and the estimated infectivity of blood products was 6.1 patients per 1000 units of blood products. It was concluded that the aetiological role of hepatitis C virus on liver cirrhosis and hepatocellular carcinoma in the endemic area of hepatitis B virus is not so important as in Western countries, and transfusion might result in an overestimated pathogenic effect of hepatitis C virus in cirrhotic patients and patients with hepatocellular carcinoma.