Some statistics show that the incidence of leukemia is about 4 per 100,000, plus various other types of blood patients have a rising trend in recent years, how to prevent the occurrence of leukemia, on the attention of everyone. Modern medical research confirms that bad mood is one of the causes of morbidity, from the perspective of Chinese medicine, emotional instability, irritability, can make the human body immune disorders, qi stagnation can lead to blood stagnation, qi stagnation and blood stagnation form the body detoxification function is reduced, and then affect the bone marrow, hematopoietic disorders, the formation of blood system diseases. The prevention of leukemia can be divided into two aspects: internal and external factors internal factors: refers to their own immunity, the body’s immunity to enhance, one by enhancing physical fitness, that is, through daily exercise, activities, so that physical fitness, physical health and vigor, enhance the ability to resist disease, the second by optimism, a positive attitude to life, gas produces a hundred diseases, that is, bad mood is the root cause of disease, since this is the case, we must learn to learn in daily life, calm mood, to avoid emotional overexcitement. Exclude worries, to avoid excessive emotional changes on the human body. External factors: Modern medicine believes that there are environmental pollution, nuclear radiation, improper medication, unknown viruses, etc. Leukemia virus may exist in a variety of normal animals and can be passed on from generation to generation, it has the potential to cause disease, once the external triggering factors can develop. Understanding the internal and external factors of blood disease formation, people have found a way to prevent blood disease, external factors to try to avoid, away from pollution sources, not arbitrary use of drugs, internal factors to regulate their emotions, have a good attitude, positive attitude to life. Now children leukemia, 2 years old – 4 years old children mostly, of which urban children account for about 1/3, resulting in the increase of urban leukemia children do not exclude the causes of pollution caused by home renovation, because the common adhesives used in renovation, paint, floor tiles, plywood, etc. will release formaldehyde, lead, stupid and other harmful substances, causing damage to the human body, weaker resistance will cause leukemia, according to the survey, the renovation of heat caused by Environmental pollution may be one of the reasons for the increase in children with leukemia. Therefore, it is recommended that the best way to decorate homes to meet the environmental protection requirements of the system of materials, before moving in, it is best to open the windows to ventilate more than a week, ask the professional indoor environmental testing department to test, qualified before living. Second, pay attention to dietary hygiene, because containing fertilizers, pesticides, vegetables, fruits and other food, easy to cause harm to the human body, and thus the onset of disease, so vegetables, fruits to wash before using raw, fertilizers, pesticides and other residues to a minimum. Do not abuse drugs, the use of chloramphenicol, cytotoxic anti-cancer drugs, immunosuppressive drugs to be careful, must have a doctor’s guidance, but also do not use long-term, in addition try not to use hair dye, which causes leukemia is 3-4 times the risk of ordinary people. It is now believed that the effects of light on the human body, some even suggest that the increased incidence of childhood leukemia may be related to exposure to light at night, in addition, care should be taken to stay away from high voltage lines, substations and microwave ovens being used. Another key to preventing leukemia is to understand some of the early symptoms of leukemia: (a) unexplained fever, anemia, bleeding, enlarged liver and spleen lymph nodes, muscle and joint pain or sternal pressure, swollen gums and vesicles that do not heal, purple skin epilepsy, etc. (2) Various kinds of blood cytopenias with unknown causes, ineffective treatment for a long time, and unexplained increase of white blood cells. (C) Severe anemia in children, treated with corticosteroids with significant effect. (iv) Leukocytosis, especially with the appearance of immature cells. Anyone with any of the above symptoms, go to the hospital early.