We performed this study to evaluate prevalence and clinical course of hepatitis B surface antigen (HBsAg)-positive and anti-hepatitis C virus (HCV)-positive renal transplant recipients. HBsAg positivity was 13.7 and anti-HCV positivity 12.8%. Before transplantation, the HBsAg positivity was observed in 83.5% of the patients, and 16.4% of the patients acquired HBsAg after renal transplantation. In the HCV group, anti-HCV positivity was observed in 47.1 % before transplantation, and 19.6% acquired anti-HCV after renal transplantation. The prevalence of chronic hepatitis in the hepatitis B virus (HBV) and in the HCV groups was not different (25.7 vs. 25.5%). Among those with chronic hepatitis in the HBV group, 4 cases progressed to fulminant hepatic failure, 1 case progressed to the end-stage liver cirrhosis, and 1 case to hepatocellular carcinoma. However, in the HCV group, no case showed progression of chronic hepatitis. The overall mortality in the HBV and HCV groups was 25.3 and 7.8%, respectively (p = 0.001). Among 20 fatal cases in the HBV group 9, cases were liver disease related, but no liver disease related death occurred in the HCV group. In conclusion, HCV as well as HBV infections are quite prevalent and important causes of posttransplant chronic hepatitis, and the clinical course of anti-HCV-positive recipients is less aggressive than that of HBsAg-positive recipients.