Generally speaking, a baby’s underarm temperature exceeding 37.3℃ is considered a fever. Normal human body temperature is relatively constant, body temperature exceeds the maximum limit of normal body temperature belongs to fever, which is often referred to as fever. Generally speaking, the axillary body temperature in 36 ~ 37 ℃ is the normal body temperature, by the environment, diet, exercise and time and other factors, body temperature will fluctuate, as long as the body temperature does not exceed 37.3 ℃, are considered normal. Therefore, the baby’s underarm temperature exceeds 37.3 ℃ is considered fever. Causes of fever in babies are more reasons, generally there is inflammation and infection in the body, commonly upper respiratory tract infection, the child in addition to fever, there will be coughing, runny nose, nasal congestion and other symptoms. The baby’s body temperature is 37.3 ℃ or more is fever, for the fever of the child, parents should give the child drink more water, with warm towels to wipe the skin, to achieve the purpose of cooling. Babies with fever are advised to seek prompt medical attention.