The prevention of leukemia is as follows: First, less exposure to radiation, such as nuclear radioactive substances, radiological examinations. Second, do not abuse drugs, avoid drugs that harm the bone marrow, such as antipyretic and analgesic, antibiotics. Third, avoid contact with chemical toxins, such as benzene, hair dyes, pesticides. Fourth, enhance resistance to reduce viral and bacterial infections. Fifth, external factors to avoid exposure to toxic substances, such as living environment, work environment, reduce the chance of bone marrow damage, reduce the chance of getting leukemia.