The process of leukemia chemotherapy in children can also produce some uncomfortable reactions and signs. Children applying chemotherapy drugs can also have many adverse reactions, such as nausea, vomiting, hair loss, loss of appetite, oral or anal mucous membrane vesicles occurring ulcers, pain and so on. Due to the seriousness and rapid development of leukemia, coupled with the complications caused by chemotherapy, such as hair loss, numbness, fatigue, fever, etc., children are prone to pessimism and frustration, and in severe cases, they may lose confidence in the treatment. Encouraging and comforting children to bravely “get through” the past is very favorable to reduce psychological pain and help recovery. Active use of symptomatic drugs, such as the use of granisetron or ondansetron and other drugs can reduce vomiting and other adverse reactions, and at the same time should pay attention to the deployment of enteral nutrients, so that the diet of each meal is small but fine, the number of meals can be a little more, to ensure that well-digested, easy to absorb.