Epstein-Barr virus (EBV)-related post-transplantation lymphoproliferative disorder (PTLD) is a life-threatening complication in patients given T-cell-depleted hematopoietic stem cell transplantation from an HLA-haploidentical relative (haplo-HSCT). We report the case of a child who developed severe EBV-related PTLD after haplo-HSCT from his mother. Despite receiving the anti-CD20 monoclonal antibody, the patient presented with intestinal obstruction due to huge abdominal lymphadenopathy, hematemesis, and nodulary pulmonary lesions. Histology showed that the lesions were due to CD20-/CD19+ large neoplastic B cells. The patient underwent double intestinal resection with partial abdominal lymphadenectomy and then received 3 monthly doses of donor-derived unmanipulated mononuclear cells. The initial dose of CD3+ cells was 3 10(5)/kg recipient body weight. The 2 additional doses consisted of 5 10(5) CD3+ cells/kg. No sign or symptom attributable to graft-versus-host disease was observed, and the patient completely cleared EBV-related lesions. The child was disease-free for 13 months after the first lymphocyte infusion. This case demonstrates that repeated infusions of controlled numbers of donor CD3+ cells cure EBV-related PTLD in haplo-HSCT without inducing graft-versus-host disease.