Cord blood for transplant is collected from the umbilical cord and donated cord blood is tested, frozen and stored for future use. Cord blood stem cell transplantation（CBT）do not have to be as closely matched as bone marrow or peripheral blood stem cell transplantations, therefore we are able to perform CBT for refractory patients at optimal timing. Here, we report a ３３ years old woman with refractory hepatosplenic T-cell lymphoma（HSTL）who achieved complete response ; CR after unrelated CBT. She complained of fever and abdominal pain, she was diagnosed with HSTL. She was refractory to several chemotherapy regimens, we planned to allogenic transplantation for her. However, she had no HLA-matched sibling donors and we were not able to find favorable unrelated donors from Japan Marrow Donor Program. Therefore, we decided to perform CBT for her. We used fludarabine（１８０mg/m2）, busulfan（１２．８mg/kg）and melphalan（８０mg/m2） as conditioning regimens and we chose tacrolimus and MMF for graft versus host disease（GVHD） prophylaxis. On day ２２ after transplantation, her neutrophil count engrafted, she suffered from acute GVHD（skin, gastrointestinal tract, grade２）, she was improved by medical treatment. She achieved CR her disease status maintained over two years after CBT. HSTL is often refractory to chemotherapy, the clinical efficacy of hematopoietic stem cell transplantation may be expected. Our case suggests that CBT may be effective and feasible option for refractory HSTL who has no favorable HLA-matched donors
