The first thing to look for in a child with high white blood cells is the age of the child. If the child is an infant between six months and two years old, their normal white blood cell range is (11.5-12) x 10^9/L. If the white blood cells are within this range, they are normal and do not need to be treated; if they are outside of the normal range, they are leukocytosis. The leukocyte increase should be combined with the child’s condition. If the child has high leukocytes along with symptoms such as fever, sore throat, cough and sputum, it is likely that the leukocyte increase is caused by an acute respiratory infection, which requires a visit to the respiratory department, where a chest X-ray and chest CT can be taken to see if there is a respiratory infection. Then give anti-infection medication, you can use penicillin, cephalosporin antibacterial drug treatment. After the anti-infection treatment, the treatment is effective and the elevated white blood cells will gradually drop to normal. In addition, if the child has anemia and bleeding in addition to elevated white blood cells, he or she should be alerted to acute lymphoblastic leukemia and needs to be seen by a hematologist.