Fever of 39 degrees in children may be related to bacterial infection or viral infection, which needs to be treated with antibiotics or antiviral medicines, along with antipyretic medicines. Children’s fever is mostly caused by bacterial or viral infections, which need to be treated with anti-infections. If the bacterial infection caused by respiratory tract, urinary tract infection and other diseases, need to actively use antibacterial drugs such as cefaclor, ceftazidime and other anti-infective treatment. For viral infections, there is no special drug treatment, but for influenza virus infection, oseltamivir phosphate can be used for antiviral treatment. A fever of 39℃ is considered high, and physical methods such as applying warm water to the child’s forehead, taking a warm bath, reducing the amount of clothing worn, antipyretic patches, antipyretic blankets, fans, and lowering the room temperature can be used to reduce the fever and make the feverish child feel comfortable. Medications such as ibuprofen suspension and acetaminophen dry suspension should also be used under medical supervision to reduce fever. All of these medications should be used under a doctor’s supervision to avoid self-medication. There are many causes of fever in children, and it is recommended to seek prompt medical attention and be evaluated and treated by a specialist to avoid delays.