OBJECTIVE To assess de novo hepatitis B virus (HBV) transmission from liver donors with HBV serum markers (HBM) to their recipients and the need for HBV vaccination before liver transplantation. METHODS A total of 108 orthotopic liver transplantations for nonviral disease and the risk of developing de novo hepatitis B based on HBMs before transplantation have been studied. Of the 108 patients, 94 met the study criteria and were divided into two groups: 27 who had HBMs before transplantation (from past infection or by previous vaccination) and 67 who had no HBM. Development of de novo hepatitis B was determined by analytical, serological, and histological parameters. RESULTS No case (0%) of de novo hepatitis B was detected in the pretransplantation HBM group, whereas there were 10 cases (14.5%) in the other group (p < 0.005). CONCLUSIONS The presence of pretransplantation HBM in liver transplant recipients protects these patients against the development of de novo hepatitis B. This is especially important considering that there is a high prevalence of donors with positive hepatitis B core antibody (especially in some countries), and that these donors transmit HBV infection to recipients without HBM in a significant number of cases. Thus, vaccination against HBV in patients who are candidates for liver transplantation is fundamental to avoid cases of de novo hepatitis B.