Fever after chemotherapy is not a good phenomenon and needs to be analyzed according to many factors. Chemotherapy will cause a large number of necrosis of tumor cells, and the necrotic tumor cells will release thermogenic sources and fever will appear. This happens mostly in the afternoon, and the body temperature will not exceed 38.5℃. In addition, chemotherapy will lead to the decrease of white blood cells and immunity of the body, and infectious fever may occur, which is mostly seen in respiratory system infection, and may show sore throat and enlarged tonsils, and in serious cases, it may lead to lung infection. In this case, treatment by anti-infective drugs is required, and protective isolation of the patient is needed to avoid aggravation of the infection if necessary. After chemotherapy, patients should make certain adjustments in their daily dietary habits, appropriately increase nutritious food, increase appetite, assist in improving the immune system of patients, improve physical fitness, and enhance the ability to resist infection.