Infection with HBV and/or HCV is believed to be a risk factor for graft loss and patient death. Furthermore, HBV and HCV have been associated with the pathogenesis of glomerular diseases in transplanted kidneys. Objective: We designed a cohort study to investigate the incidence of post-renal transplant hepatitis and its outcome on renal dysfunction. Fifty eight renal transplant recipients who received a living (n=37) or cadaveric (n=21) kidney transplant at Namazee Hospital, Shiraz University of Medical Sciences participated in the study. Each individual sampled 1 week before up to 2 weeks post transplantation. The patients were then sampled every 4 weeks up to 52 weeks after transplantation. Serum creatinine and aminotransferase levels were measured with standard automated analyzers. Anti-HCV was determined using third generation enzyme immunoassay. The reverse transcriptase-polymerase chain reaction (RT-PCR) technique was used to assay HCV RNA. Hepatitis B surface antigen (HBsAg) and anti-HBc antibody were determined with an enzyme immunoassay. Detection of HBV-DNA was performed on seropositive patients by polymerase chain reaction (PCR). Anti-HCV was not detected in serum samples of any cases before transplantation. However, 10 (17.2%) of 58 recipients tested positive for antibody to HCV post-transplantation and remained positive during study time. five (50%) of these 10 patients had abnormal liver function test. HCV-RNA was detected in 2 (20%) of the patients. HBsAg was not detected in serum samples of any cases before transplantation. However, anti-HBc antibody was determined in serum samples of 6 (16.2%) of 37 living donors and in 8 (13.8%) of 58 recipients before transplantation respectively. Overall, 10 (17.2%) of 58 recipients were found positive for anti-HBc antibody post transplantation. HBsAg was found in 1 (1%) of 10 recipients post transplantation. After transplantation, 8 of 10 patients had maintained normal ALT levels for the entire study period, whereas the other 2 patients developed ALT elevations. In general, the mean level of ALT in HBV infected recipients was significantly higher than living donors. No HBV DNA was detected in serum samples of the patients with anti-HBc or HBsAg positive. The incidence of post renal transplantation HCV infection is higher than HBV infection. HCV and HBV infection do not appear to influence renal dysfunction within a short-time follow-up in renal recipients. Nevertheless, long-term development of chronic liver disease or graft loss is not impossible.