Three patients with malignant gliomas were treated with the high-dose chemotherapy with autologous bone marrow transplantation. In the first two cases, the autologous bone marrow cells were stored and transplanted 48 hours after single high-dose of ACNU therapy. (800 mg/m2, 600 mg/m2) One died of intratumorous bleeding on the 18th day and the other of pulmonary fibrosis on the 35th day. Their autopsy specimens revealed that most of the tumor had degenerated with only a small portion of viable cells. The third patient was treated with high-doses of ADM (100 mg/m2), VCR (1.5 mg/m2), DDP (80 mg/m2), and EX (800 mg/m2) within eight days, prior to the cryopreserved bone marrow transplantation. Granulocytes and platelets began to increase from ten days after the transplantation and became normalized within three weeks thereafter. CT scan performed six months after the chemotherapy revealed 89% reduction of the tumor. The number of our cases is still small, but the results showed that the autologous bone marrow transplantation made high-dose chemotherapy possible. The necessity for cryopreservation of bone marrow was discussed.