Abstract： Objective To explore the use of antithymocyte globulin in peripheral blood stem cell transplantation from HLA-identical sibling donors. Methods Fifty-seven adults with hematological malignancy were treated with a first myeloablative matched related donor peripheral blood stem cell transplantation with pretransplantation of ATG. All patients received modified Bu/cy conditioning regimen or Cy/TBI conditioning regimen. GVHD prophylaxis protocol included Rabbit ATG (thymoglobulin, genzyme),Cyclosporin A, methotrexate and mycophenolate mofetil. Results All patients underwent engraftment with neutrophils and platelets. Incidence of aGVHD was 36.8 %. Gades Ⅰ - Ⅱ was observed in 31.6 %. Grade Ⅲ was 5.2 %. Grade Ⅳ was not seen. Incidence of cGVHD was 33.3 %, including two extensive cGVHD cases.Infection had occurred in twenty-two patients during transplantation. Twenty-nine (50.9 %) patients occurred CMV reactivation. The 5-year estimated OS is 71.35 %. The 5-year estimated DFS is 68.61%. Conclusion Pretransplantation with low dose ATG given to recipients undergoing MRD PBCT may result in less aGVHD and cGVHD. No cases of posttransplantation lymphoproliferative disease was observed. Significant morbidity and mortality from opportunistic infection were not seen. Relapse remains a problem among high-risk patients.