A 17-year-old Japanese boy with severe aplastic anemia was treated with oxymetholone and pred-nisolone for 9 weeks without improvement. He then received 2 courses of bolus methylprednisone therapy without improvement and developed a severe liver dysfunction due to this bolus therapy. He had no HLA-compatible sibling for a bone marrow transplantation, and antithymus globulin was not available. A total of 7 lymphocytapheresis treatments were performed, using an IBM 2997 cell separator, over a period of 9 weeks. Hematological and clinical improvement were noted and felt to be related with these lymphocytapheresis treatments, and further therapy was not required. Three years have past since the patient has undergone lymphocytapheresis, and he remains in good health. Thus, lymphocytapheresis may be an alternative therapy for cases of severe aplastic anemia for those patients who have no compatible donor for bone marrow transplantation and when antithymus globulin is not available.