Autologous blood stem cell transplantation (ABSCT) has been increasingly used in the treatment of malignant diseases. With the use of hematopoietic cytokines, collection of peripheral blood stem cell (PBSC) has become easier. Contamination of PBSC with tumor cells is supposed to be reflecting the amount of residual tumor cells in the host. G-CSF combined conditioning regimen seems to be effective for ANLL in complete remission (CR) probably by in vivo purging of residual leukemic cells. From our preliminary results, ABSCT can be used as the treatment of choice for standard risk ANLL, and aggressive non-Hodgkin's lymphoma. To clarify the curative potential of ABSCT, prospective clinical trial consisting of remission induction, consolidation of CR, PBSC harvests, and marrow-ablative therapy for ABSCT will be required.