The impact of allelic HLA matching in patients with AML and myelodysplastic syndrome (MDS) who receive allogeneic PBSC after a reduced-intensity conditioning (RIC) regimen is unclear. From January 2000 to December 2010, 108 consecutive patients with AML (n=63) and MDS (n=45) received PBSC after RIC in our center, either from siblings (n=70) or from matched unrelated donors (MUD; 10/10 high resolution, n=38). Conditioning regimen was fludarabine based in 95% of patients and GvHD prophylaxis was mostly cyclosporine plus mycophenolate. Patient characteristics were similar between sibling and MUD for age (median 57 years), gender and disease distribution. Conditioning regimen (more anti-thymocyte globulin (ATG) in MUD), donor age (younger for MUD) and number of CD34+ cells infused (higher in MUD) were different. The median follow-up was 36 months (range 2-72). Engraftment, GvHD, TRM, relapse rate and OS at 3 years were comparable between sibling and MUD. After adjustment for age, cytogenetic risk, ATG and number of CD34+ cells infused, donor type still did not influence OS. In patients with AML or MDS, HSCT from MUD using PBSC after a RIC regimen led to similar outcomes than from Siblings.