Fever in children may be related to non-infectious factors, such as after exercise, high indoor temperature, etc., or infectious factors, such as bacterial, viral and mycoplasma infections. 1. Non-infectious factors: If the symptoms of body fever in children are relatively simple and do not exceed 37.3℃ when measured by a thermometer, it may be related to related sports, such as running, playing basketball, etc., or it may be related to factors such as high indoor temperature. 2. Infectious factors: children with fever if the use of thermometers to measure more than the standard degree, we need to be vigilant about bacterial, viral, mycoplasma and other factors that cause fever, but also accompanied by coughing, depression, loss of appetite and other adverse reactions. Children may also have other causes of body heat, it is recommended to go to the hospital in time to carry out relevant examinations, clear cause of the disease after active symptomatic treatment.