AML patients (total 129; median age =50 years; range 16-72) in first CR received BU and melphalan (BU/Mel) as conditioning regimen before auto-SCT. In all, 82 patients (63.6%) received PBSCs and 47 patients (36.4%) received BM cells. The distribution of cytogenetic categories was conventionally defined as favorable (15.5%), intermediate (60.1%) and unfavorable (24.3%). With a median follow-up of 31 months, the 8-year projected OS and disease-free survival (DFS) was 62 and 56% for the whole population, respectively. The relapse rate was 46% and the non-relapse mortality was 4.65%. Although PBSC transplantation led to a faster hematological recovery than BM transplantation, in univariate analysis the stem cell source, cytogenetics and different BU formulations did not significantly affect OS and DFS, whereas age and the number of post-remission chemotherapy cycles did have a significant effect on the clinical outcome. Multivariate analysis identified age <55 years as the only important independent predictor for OS and DFS. Our data suggest that BU/Mel, being associated with a low toxicity profile (mainly mucositis) and mortality, is an effective conditioning regimen even for high-risk AML patients in first CR undergoing auto-SCT.