Lamivudine has been shown to prevent de novo hepatitis B virus (HBV) infections in liver transplantation (LT) patients receiving hepatitis B core antibody-positive (HBcAb(+)) grafts, but it may produce long-term resistance. Adefovir dipivoxil (ADV) might be effective in preventing de novo hepatitis and resistance. A single-center, prospective trial was conducted with 16 adults (10 men and 6 women, mean age = 54 ± 11 years) who underwent LT with HBcAb(+) grafts between September 2007 and October 2009. After LT, patients were given ADV [10 mg daily (adjusted for renal function)]. No hepatitis B immune globulin was administered. At LT, all graft recipients were hepatitis B surface antigen-negative (HBsAg(-)), 38% were surface antibody-positive (HBsAb(+)), and 50% were HBcAb(+). The median follow-up after LT was 1.8 years (range = 1.0-2.6 years). All recipients had undetectable HBV DNA (<40 IU/mL) after LT until the end of follow-up. One recipient (6%) who was HBsAb(-) and HBcAb(-) before LT became HBsAg(+) after 52 weeks. One recipient was switched from ADV to entecavir for chronic renal insufficiency, and 19% of the patients had renal dose adjustments. There was a nonsignificant trend of increasing creatinine levels over time (1.2 mg/dL at LT, 1.3 mg/dL 1 year after LT, and 2.0 mg/dL 2 years after LT, P = 0.27). A comparison with a control cohort of LT recipients with hepatitis C virus who did not receive ADV showed no difference in the creatinine levels at LT or 1 year after LT. In conclusion, ADV prophylaxis prevents HBV replication in recipients of HBcAb(+) livers but does not fully protect recipients from de novo HBV. Long-term follow-up is needed to better determine the risk of de novo infection.