When a child has a fever of 39 degrees or more, it may be related to non-infectious and infectious factors, and can be relieved by giving symptomatic and causative treatments. 1. Symptomatic treatment: children with a fever of 39 degrees, need to cooperate with the doctor to give ibuprofen, acetaminophen and other antipyretic and analgesic medication, so as to alleviate the adverse symptoms of fever in children. At the same time, drink more water, with physical cooling, such as warm water bath forehead, wrists, calves to help dissipate heat or head placed fever patches and so on. 2. Treatment of the cause: small children with a fever of 39 degrees, may be due to non-infectious factors, such as leukemia, connective tissue disease, etc., need to actively target the original disease for treatment. In addition, viruses, bacteria, mycoplasma and other infections may also cause fever related, need to actively find the cause of fever, give appropriate anti-infection treatment. When a child has a fever of more than 39 degrees, it is recommended to consult a doctor in time. The medication should be in accordance with the doctor’s instructions, and should not be used blindly, in order to avoid the adverse effects.