Acute leukemia is common in children under 10 years old. It usually starts rapidly, and the early symptoms often include headache, pallor, lack of energy, weakness, loss of appetite, nasal or gum bleeding, etc. A few children have fever and bone and joint pain as the first symptoms, and it is also often accompanied by the following symptoms: 1. Petechiae or petechiae, nasal bleeding, gum bleeding, gastrointestinal bleeding, and hematuria, etc. Intracranial hemorrhage is less common and can cause death; 3. Fever: mainly related to leukemia fever and infection, with hypothermia, irregular fever, persistent hyperthermia, flaccid fever and other fever types common, usually without chills, and antibiotic treatment is ineffective; 4. Organ enlargement: generally early liver, spleen and lymph node enlargement can appear, the enlarged parts are soft, smooth with pressure pain. Superficial lymph nodes are commonly enlarged in the neck, submandibular, axillary and inguinal areas; 5. Bone and joint pain: some children may have joint pain in the knee, shoulder, wrist and ankle joints as the first symptom, which may also be accompanied by sternal pressure pain. When the above symptoms appear, it is recommended to seek medical attention immediately. A general peripheral blood picture shows a decrease in red blood cells, hemoglobin and other blood cells, while about 50% of patients have a significant increase in white blood cells. Bone marrow examination can be an important basis for confirming the diagnosis and judging the efficacy of the disease, which shows an increase in leukemic cells and a decrease in juvenile red blood cells and megakaryocytes in the child.