The normal body temperature of infants should be between 36.3°C and 37.3°C. The body temperature of newborns should be slightly higher than that of adults because the center in the infant’s brain that controls thermoregulation is still immature and its ability to control body temperature is not strong enough, and body temperature tends to fluctuate, causing the infant’s body temperature to be affected by the environmental temperature. For example, the body temperature of infants is often higher in the evening than in the early morning; it also increases temporarily after eating, crying, or exercising; it also increases if the clothing is too thick and the room temperature is too high. If an infant has temporary temperature fluctuations of a small magnitude as described above, it is usually not considered pathological as long as the infant is in good general condition, lively and has no other symptoms or signs. However, the infant’s body temperature should not exceed 37.5°C even if external factors influence it, and exceeding it is a fever. If the baby’s fever is below 38.5°C, it is recommended to use only physical cooling methods, such as warm water baths, appropriate removal of extra clothing, and drinking more water. If it is above 38.5℃, it is best to give your baby fever-reducing medicine in time. If the baby is within 3 months of age at this time, it should be sent to the hospital for examination and treatment. In short, infants with fever must be taken seriously and heat treatment must be promptly withdrawn to prevent the occurrence of induced febrile convulsions or bronchopneumonia.