Matched sibling bone marrow transplantation (BMT) in severe aplastic anemia (SAA) has been known as the treatment of choice in children and young adults. To overcome graft failure, second stem cell transplantation showed good results in previous studies. Here we report two cases of aplastic anemia patients with late graft failure and resulted in successful complete recovery after selective CD34+ cell boost infusion. The patients previously underwent allogeneic BMT from HLA-matched sibling donors and the engraftment was achieved although their CBC started to decrease respectively 3 months and 11 months after transplantation. Both patients received selective CD34+ cell infusion without additional conditioning therapy. Their CBC showed significant improvement and they are doing well without transfusion or complications. From this study we suggest that selected CD34+ cell boost treatment can be a promising curative treatment for late graft failure after matched sibling BMT in SAA patients.