The treatment of pediatric acute leukemia is mainly a combination therapy based on chemotherapy. The main purpose of chemotherapy is to kill leukemia cells, relieve the symptoms caused by leukemia cell infiltration, relieve the condition and consolidate the therapeutic effect, reduce drug resistance and cure. 1.Supportive therapy (1) Anti-infection: for bacterial, fungal and viral infections, antibiotics, antifungal drugs and antiviral drugs should be used reasonably as prescribed by doctors. (2) Component blood transfusion: red blood cells can be transfused in cases of obvious anemia; platelet concentrate can be transfused in cases of bleeding due to thrombocytopenia. Immunoglobulin can be transfused intravenously if necessary. (3) Others: in the course of treatment, nutrition should be increased. When there is fever and bleeding, bed rest should be provided. Pay attention to oral hygiene, prevention and treatment of disseminated intravascular coagulation. 2. Chemotherapy (1) Induction therapy: Combine various chemotherapy drugs (such as vincristine, Zoerythromycin, etc.) to kill leukemia cells to the maximum extent. (2) Consolidation therapy: continue to combine chemotherapeutic drugs (e.g. cyclophosphamide, cytarabine, etc.) to kill the remaining leukemia cells. (3). Prevention of extramedullary leukemia: central nervous system leukemia and testicular leukemia both lead to bone marrow relapse and treatment failure, therefore, effective prevention of extramedullary leukemia is one of the key measures for children with acute leukemia to achieve long-term survival. If a baby is found to have leukemia, it should be treated as early as possible.