Allogeneic bone marrow transplantation (BMT) was carried out on a 5- year-old boy with congenital hypoplastic anemia (CHA), who did not respond to corticosteroids and who was displaying signs of progressive hemosiderosis. Pretransplant preparation had to be modified because respiratory failure and cerebral edema supervened. This preparatory regimen consisted of busulfan (2 mg/kg for four days), cyclophosphamide (50 mg/kg for one day), and total body irradiation (750 rad). Hemopoiesis was completely restored and is still maintained 650 days after transplantation. This is the second published report on the use of BMT to treat a patient with CHA, and it is the first time it has resulted in long-term survival. BMT should be considered for patients with CHA who do not respond to corticosteroids.