Patients who have relapsed 8 years after leukemia transplantation can be treated with chemotherapy, immunotherapy, or undergo a second bone marrow transplant. 1. Relapsed acute myeloid leukemia (1) High-dose cytarabine combination chemotherapy: for those who are <55 years old and have good supportive conditions. (2) Enabling combination chemotherapy with new drugs: e.g. fludarabine, vinblastine, and desmethoxazole. (3) For older age or secondary AML, treat with demethylating drugs, such as decitabine. (4) Immunotherapy: non-cleared marrow hematopoietic stem cell transplantation, donor lymphocyte infusion, myeloid monoclonal antibodies, etc. 2. Relapsed lymphoblastic leukemia (1) Use new anticancer drugs and combine them with other anticancer drugs, such as cedarbenazine. (2) Medium or high dose cytarabine or methotrexate can be considered. (3) If available, a second hematopoietic stem cell transplantation is feasible. After leukemia transplantation, if the blood test results are abnormal, it is recommended to consult a doctor in time to clarify the cause of the disease and to carry out targeted treatment or therapy with the help of the doctor. Avoid blind self-medication.