Chronic liver infections related to hepatitis B and C viruses are a common problem in renal transplant patients with a prevalence of 1.5 to 50% in different countries. There is no uniform agreement regarding their influence on the incidence of acute rejection, graft outcome and survival of renal transplant patients. We retrospectively evaluated the influence of antiHBc, antiHCV and HBsAg positive status; gender; age over 50 years of age at the time of transplantation; pre and postransplantation alaninaminotransferase (ALT) elevation; acute rejection; type of graft; number of transplants; and maintenance and induction immunosuppression treatment on the incidence of acute rejection and both graft and patient survival in the population transplanted in our center between 1991 and 1998. The univariate analysis showed that antiHCV, HBsAg and antiHBc status, more than one renal transplant and one or more episodes of acute rejection were associated with diminished graft survival; and being over the age of 50 at the time of transplantation was also associated with diminished patient survival. In the multivariate analysis HBsAg positive and one or more episodes of rejection were associated with a diminished graft survival, and none of the variables studied was associated with diminished patient survival. In conclusion antiHCV and HBsAg positive status was associated with an increased risk of losing the transplanted kidney, and HBsAg positivity was associated with an increased risk of death, but this was not a statistically significant association.