Initial symptoms of leukemia include fever, bleeding and anemia, enlarged liver, spleen and lymph nodes, bone and joint pain, etc. 1. Unexplained fever: fever is a common symptom of leukemia, most of the children will show unexplained fever in the early stage, usually the treatment effect is not good, and the type of fever is not certain, then parents need to pay attention to it, and take the children to the hospital for a comprehensive examination as soon as possible. 2. Bleeding and anemia: some children will have different degrees of bleeding, often manifested as nasal bleeding, subcutaneous petechiae, bleeding gums, and even bleeding in urine and stool. Children with leukemia have signs of bleeding and impaired hematopoietic function, and are prone to symptoms of anemia, such as fatigue, pale nail beds, shortness of breath, etc. 3. Enlarged liver, spleen and lymph nodes: leukemia cells will infiltrate and cause enlarged liver and spleen, and there will be enlarged lymph nodes in the neck, armpit and groin, but without pressure pain. 4. Bone and joint pain: the proliferation of white blood cells and leukemia cells in the bone marrow will compress and destroy the bone, resulting in bone and joint pain, and the site of pain is not fixed. Once the above manifestations occur in children, they need to go to the hospital in time to get a clear cause and timely treatment to avoid delaying the condition.