Objective To study the outcome of HLA-identical hematopoietic stem cell transplantation ( HSCT) for severe aplastic anemia (SAA). Methods Twenty patients diagnosed with SAA received allogeneic HSCT from HLA-identical donors ( 17 from siblings and 3 from unrelated donors) between January 2000 and November 2008. Conditioning regimen consisted of cyclophosphamide ( Cy) and anti-thymocyte immunoglobulin (ATG). The patients were administrated with G-CSF-primed bone marrow (G-BM) and mobilized peripheral blood (G-PB) as grafts from the sibling donors or only G-PB from the unrelated donors. Results The median infused number of mononuclear cells and CD_(34)~+ cells were 7. 89 (4-14.21) × 10~8/kg and 2.60 (0.81-4.45) × 10~6/kg. All the patients got engraftment with 100% donor chimerism. The median time of neutrophil and platelet engraftment were 14 ( 11-20) d and 12 (8-108 )d respectively. The cumulative incidence rate of acute GVHD at 100 d was 16% (grade I : 3 cases,grade II :3 cases). Chronic GVHD occurred in 7 of the 19 evaluable cases (4 limited, 3 extensive). Till February 28, 2009, with a median follow-up of 18 months, 17 patients were alive and the overall survival rate was 82. 5%. Conclusion The study confirms that using G-PB with or without G-BM as graft after Cy + ATG conditioning results in excellent outcome of HLA-identical HSCT in patients with SAA.