The efficacy of minimal residual disease (MRD)-directed immunotherapy,including interferon-α (IFN-α) treatment and chemotherapy plus granulocyte colony-stimulating factor-primed donor leukocyte infusion (chemo-DLI),was investigated in patients with high-risk myelodysplastic syndrome (MDS) who were MRD-positive after allogeneic hematopoietic stem cell transplantation (allo-HSCT).High-risk MDS patients who received non-T-cell-depleted allo-HSCT at the Peking University Institute of Hematology and were MRD-positive after ailo-HSCT were studied (n =47).The MRD-positive status was considered if leukemia-associated aberrant immune phenotypes or Wilms’ tumor gene 1 expression is present in a single bone marrow sample.The cumulative incidence of the relapse and non-relapse mortality 2 years after immunotherapy were 14.5％ and 21.4％ (P=0.377)and 9.1％ and 0.0％ (P=0.985) for patients in the IFN-α and chemo-DLI groups,respectively.The probability of disease-free and overall survival 2 years after immunotherapy were 76.4％ and 78.6％ (P =0.891) and 84.3％ and 84.6％ (P=0.972) for patients in the IFN-α and chemo-DLI groups,respectively.Persistent MRD after immunotherapy was associated with poor survival.Thus,the MRD-directed immunotherapy was effective for patients with high-risk MDS who were MRD-positive after alIo-HSCT,and the efficacy was comparable between chemo-DLI and IFN-α treatment.