A 5-year-old child’s body temperature of 35.2 ℃ can be caused by measurement errors, normal physiological phenomena, and diseases. 1. Measurement error: The thermometer used for measurement may be damaged, resulting in inaccurate measurement of body temperature. 2. Normal physiological phenomenon: when the child is in a cold environment, the core temperature is not affected, but the body surface heat loss is faster, so the temperature measured from the body surface is low, which is a normal phenomenon. 3. Disease: Usually, in addition to a drop in body temperature, there is also a combination of chills, fatigue, loss of appetite, cough, abdominal pain and other abnormalities, when combined with the above abnormalities, the possibility of upper respiratory tract infections, pneumonia and other diseases caused by the consideration. In the case of determining the child’s body temperature measurement is correct, for the child’s body temperature drop should be good warm measures, such as suspected disease causes, should also be timely to the hospital or clinic, in order to avoid delays in the condition.