The general principle of treatment is to destroy leukemic cells and control the massive proliferation of leukemic cells, and to relieve the various clinical symptoms caused by leukemic cell infiltration. Treatment should be individualized according to the patient’s risk stratification and the patient’s physical condition. I. Supportive treatment: 1. Rest and diet: In case of fever, severe anemia or significant bleeding, bed rest and a high-calorie, high-protein and high-vitamin diet should be taken. 2. Prevention of infection: Severe infection is the main cause of death in patients with acute leukemia, so it is crucial to prevent and treat infection. Attention should be paid to oral, nasopharyngeal and anal skin hygiene to prevent oral and nasal mucous membrane rupture and bleeding; 3. Control bleeding: chemotherapy is taken for leukemia so that the disease is in remission is the key to correct bleeding. Those with severe bleeding tendency, or hyperthermic patients with low platelets should be treated with platelet replacement transfusion; 4. Psychotherapy: psychotherapy for acute leukemia is crucial, and the psychological comfort of medical staff and patients’ families is an important factor in the success of treatment. Second, chemotherapy Chemotherapy includes induction remission therapy and post-remission therapy. The purpose of chemotherapy is to try to control the proliferation of leukemic cells and maximize the killing of leukemic cells, but while killing leukemic cells, it can also kill normal cells, especially those that proliferate faster, such as mucosal cells of the digestive tract, causing gastrointestinal side effects (nausea, vomiting, abdominal pain, diarrhea, loss of appetite, etc.); at the same time, it can inhibit the proliferation of normal hematopoietic stem cells in the bone marrow, causing myelosuppression, i.e. It can also inhibit the proliferation of normal hematopoietic stem cells in bone marrow and cause myelosuppression, i.e., decrease in leukocytes, hemoglobin and platelets, and lead to corresponding clinical complications, such as infection, severe anemia and severe bleeding. Prevention and treatment of central nervous system leukemia Central nervous system leukemia, i.e., leukemia cells infiltrating the meninges or brain parenchyma, can occur before, during, or during remission of leukemia, and can be a precursor to bone marrow relapse, or even the only place where relapse occurs. Its prevention and treatment include intrathecal injection of chemotherapeutic drugs (methotrexate, cytarabine, dexamethasone) by lumbar puncture and cranial and spinal cord irradiation. Treatment of other extramedullary leukemias Extramedullary leukemia can be seen in bone, periosteum, orbit, paranasal sinus, genitourinary tract, mediastinum, pleura or peritoneum, skin, breast, respiratory tract, gastrointestinal tract, etc. The incidence is about 5%. The treatment of extramedullary leukemia includes local radiotherapy and systemic chemotherapy. Bone marrow transplantation is an option for refractory acute leukemia or poorly prevented leukemia. Bone marrow transplantation includes autologous peripheral hematopoietic stem cells, allogeneic bone marrow, and umbilical cord blood transplantation. Autologous bone marrow transplantation has the risk of high relapse rate, and allogeneic bone marrow transplantation has the risk of post-transplant rejection.