Three patients (2 with high malignant non Hodgkin's lymphomas in partial remission and 1 with acute myeloblastic leukemia in 2nd complete remission) underwent autologous peripheral blood stem cell transplantation (APBSCT). The minimal number of mononuclear cells and CFU-GM collected was 6.18 x 10e8 and 19.77 x 10e4/kg b.w., respectively. Conditioning chemotherapy consisted in BEAM and CVB protocols in non Hodgkin's lymphoma (NHL) patients and busulphan and cyclophosphamide in acute myeloblastic leukemia (AML) patients. All patients achieved complete remission. Bone marrow biopsy performed on day 14 showed complete engraftment. The time to reach 1 x 10e9/l WBC, 0.5 x 10e9/l neutrophil granulocytes and 50 x 10e9/l platelets was no longer than 11, 15 and 8 days, respectively. No major infectious episodes were evident during aplastic phase; fever greater than 38 degrees C was observed in two patients not lasting longer than 2 days. All patients are still in complete remission and continue to have normal hematological values (follow-up lasting 8+ and 3+ months for NHL patients and 4+ months for AML patient).