We report a case of successful umbilical cord blood transplantation (CBT) for Epstein-Barr virus (EBV)-associated lymphoproliferative disease (LPD) in a 6-year-old girl. The patient had hemophagocytic syndrome with excessive circulating levels of EBV DNA that was refractory to immunochemotherapy. Multiple hepatosplenic lesions favored the diagnosis of EBV-associated LPD, although the aggressive course precluded the histopathologic diagnosis. Unrelated CB cells mismatched at 1 HLA locus were infused after patient conditioning with 900 mg/m2 etoposide, 2 g/m2 cytarabine, 16 mg/kg busulfan, and 200 mg/kg cyclophosphamide. Complete chimeric status was obtained on day 19 posttransplantation. Drug fever and acute graft-versus-host disease of the skin (grade II) were the major complications. A transient increase of EBV DNA 1 year after CBT indicated a primary EBV infection of the donor cells. The patient is alive with no evidence of disease 27 months after CBT. There has been no previous report of successful CBT for EBV-related LPD/lymphoma. CBT can be a curative treatment for the disease, even if no viral memory has been set in the stem cell source.