A 5-year-old boy with beta-thalassemia major received an unrelated umbilical cord blood transplantation (URD-UCBT). The URD-UCB was six antigen HLA matched. The infused cell dose was 7.5 x 10(7)/kg nucleated cells. Conditioning included busulfan 20 mg/kg, cyclophosphamide 200 mg/kg, fludarabine 150 mg/kg, thiotepa 6 mg/kg, and antithymocyte globulin 90 mg/kg. The post transplant complications were mild hepatic veno-occlusive disease, acute GVHD grade III, and CMV interstitial pneumonia. The subject has been ex-thalassemic for more than 20 months post transplant. The chronic GVHD was limited and could be controlled by methylprednisolone combined with mycophenolate. This is the first successful report of an unrelated umbilical cord blood transplantation for beta-thalassemia major from China.