To explore feasibility and efficacy of unrelated HLA matched donor marrow transplantation in treatment of myelodysplastic syndrome, one case (male, 31 years old) of myelodysplastic syndrome-refractory cytopenia with multilineage dysplasia (MDS-RCMD) has been received unrelated HLA-matched donor transplantation. Busulfan, cyclophosphamide, Ara-C, MeCCNU and antithymocyte globulin (ATG) were used for preparative regimen. Mycophenolate mofetile, cyclosporin A and short-term methotrexate were used for graft-versus-host disease prophylaxis. The results showed that neutrophil of > 0.5 x 10(9)/L, platelet of 58 x 10(9)/L and hemoglobin of 114 g/L were observed at 10, 20 days and 3 months respectively post transplantation. Disease-free survival without GVHD was 9 months. In conclusion, unrelated HLA matched donor marrow transplantation is an effective approach for treatment of patients with MDS.