Chronic granulomatous disease is one of the rare congenital immunodeficiency which can be cured by hematopoietic stem cell transplantation. Previous myeloablative conditioning regimen has problems related to the severe toxicities, and non-myeloablative conditioning regimen has the risk of graft failure. Recently, reduced-intensity myeloablative conditioning regimen with busulfan and fludarabine was used usually in leukemia patients.