Leukemia is a malignant proliferative disease of the hematopoietic system. The early symptoms of leukemia in 2-year-old babies often lack specificity and can be mainly manifested as anemia, fever, bleeding, enlarged lymph nodes and damage to the central nervous system and pain. If leukemia is suspected in the presence of the following symptoms, prompt medical attention should be sought for a clear diagnosis and early treatment.1. Anemia: manifested as pale color of the face, lips and nail bed, and decreased appetite. Some of them will show shortness of breath and easy sweating after activity. 2. Fever: often shows irregular fever and also symptoms of respiratory tract infection, such as coughing, coughing and shortness of breath. It may also be accompanied by symptoms of gastrointestinal infection, such as abdominal pain, diarrhea, nausea, vomiting, etc.; 3. Bleeding: Symptoms of easy bleeding from the nose or mouth, or bleeding spots on the skin and mucous membranes, such as petechiae and petechiae. In severe cases, symptoms such as coughing up blood or gastrointestinal bleeding may also appear; 4. Lymph node enlargement: As leukemia cells invade the lymph nodes, they may manifest as enlarged lymph nodes in the neck with local lumps. Or the liver and spleen may be enlarged, such as the appearance of obvious abdominal bulging and bloating; 5. Damage to the central nervous system: children may have headache, vomiting, or even convulsions and coma; 6. Pain: manifested as bone and joint pain, partly accompanied by sternal pressure pain.