Strictly speaking, 39℃ is not considered a high fever, but a moderate fever. However, it is necessary to promptly visit the general internal medicine department for examination and give appropriate treatment to avoid other complications. Clinically, fever is divided into four degrees according to the temperature: first, low fever, i.e. 37.3℃-38℃. Second, moderate fever, which is 38.1℃-39℃. Third, high fever, which is 39.1℃-41℃. Fourth, ultra-high fever, which is a body temperature above 41℃. So 39℃ is moderate fever, not considered hyperthermia. But it is close to hyperthermia and needs to be taken seriously enough. It is recommended to seek medical consultation in hospital in time, and after clarifying the cause, take antipyretic medication under the guidance of the doctor, and if necessary, injections or infusion treatment. Patients should pay more attention to rest, avoid fatigue, pay attention to a light diet, avoid cold, greasy, spicy, stimulating food, you can eat fresh vegetables and fruits to meet the body’s requirements for vitamin C, to improve the body’s immunity and resistance.