A 62-year-old man with transfusion-dependent severe aplastic anemia received immunosuppressive therapy (IST) with rabbit antithymocyte globulin and cyclosporine A in April 2010. However, his transfusion dependency did not improve. As more than 100 red blood cell (RBC) transfusions had been performed, he was administered iron chelation therapy (ICT) with deferasirox (DFX) to improve iron overload starting in July 2011. Consequently, both RBC and platelet transfusion dependency gradually improved concomitant with a decrease in serum ferritin. The bone marrow (BM) biopsy findings before administration of DFX showed severe iron accumulation and strong positive immunostaining for 8-OHdG, a marker of oxidative stress due to free iron. One year after ICT, the number of BM hematopoietic cells was increased and both iron deposition and oxidative stress were decreased. These findings suggest that DFX may contribute to hematological improvement in patients with IST-refractory aplastic anemia.