Three-year-old babies have a fever of 39 degrees and viral or bacterial infections, can be through the medication to reduce fever, while with physical cooling and other ways to reduce fever. 1. medication: three-year-old baby fever 39 degrees, can be taken under the guidance of the doctor to reduce fever medication, such as ibuprofen suspension, acetaminophen, etc. for treatment, to avoid the occurrence of high temperature convulsions. 2. Physical therapy: three-year-old baby fever 39 degrees, in the drug fever at the same time, can be combined with physical cooling way to relieve symptoms, such as soaking in warm water bath, warm water bath, etc., to alleviate the symptoms of the baby’s fever. At the same time should be appropriate to let the baby drink more water, reduce the amount of clothing on the body, to help dissipate heat, should also do a good job of temperature monitoring, pay attention to observation and so on. If the baby continues to have a high fever or recurrent fever, parents are advised to bring the child to the doctor for a detailed examination to clarify the cause of the fever and then carry out targeted treatment. The use of medication should follow the doctor’s instructions.