Fever is a common symptom after surgery, and most patients will have a temperature of more than 37°C. Whether the postoperative fever is serious or not depends on the patient’s specific situation, such as whether other symptoms are also present and whether complications exist. There are various causes of postoperative fever. First of all, postoperative fever is not necessarily accompanied by infection, and if the fever occurs in the first 24 hours after surgery, it is mostly considered to be a transfusion reaction. If transfusion reaction can be excluded, streptococcal infection or aspiration pneumonia is mostly considered. Secondly, prolonged surgery, extensive tissue damage, drug allergy, etc. can also cause fever. Postoperative fever is a self-protective mechanism of the body, so there is no need to worry too much. The body consumes more energy than normal after the fever, and the body is weak after surgery, so nutrition should be increased, but it is better to have easily digestible food. However, consideration needs to be given to the anesthesia of the surgery. If the surgery has just been performed and the lower body is anesthetized, or if the anesthesia is general, you need to wait until the intestines resume peristalsis (that is, exhaustion) before you can take liquid food. Most importantly, it is important to have an adjusted state of mind. Some patients become nervous once they have a fever after surgery, which exacerbates the abnormal increase in body temperature. Therefore, do not be anxious about the postoperative fever, but listen to the doctor’s advice and actively cooperate with the doctor’s treatment. In addition, the healing of the wound and other accompanying symptoms should be closely observed to prevent the occurrence of surgical complications such as wound infection. In short, if the body temperature does not exceed 38℃, it can be left untreated. If it is higher than 38.5℃ and the patient feels uncomfortable, physical cooling, symptomatic treatment and close observation can be given. Drink plenty of water and eat a diet based on easily digestible food such as thin rice, soup and noodles.