In general, the normal body temperature of children is between 36-37 degrees Celsius, and a temperature lower than 36 degrees Celsius usually belongs to hypothermia, which may be caused by measurement error, or related to low ambient temperature, inhibition of thermoregulatory centers, or overdose of antipyretic medication, etc., and needs to be analyzed in detail. If the temperature is low because the measurement has not been taken for a sufficient period of time, or the mercury tip or electronic probe of the thermometer has not been placed at the top of the armpit, or the armpit has not been clamped down, then it is sufficient to re-measure the temperature in the correct way. Secondly, prolonged exposure to cold environment, or frequent use of antipyretic drugs may also occur. If the above factors are ruled out, it is necessary to consider that it is caused by disease factors, and may suffer from diseases that cause hypothermia, including pathogenic infections, or disorders of thermoregulation of the central nervous system, as well as diseases of the endocrine system, such as hypothyroidism, hypoadrenocorticism, etc., which require timely treatment of the primary disease. If a child’s temperature is between 35-36 degrees, but there are no symptoms such as mental depression or poor feeding, no special treatment can be needed, otherwise it is recommended to go to the hospital.