The 8-year-old boy’s temperature fluctuates in the past two days may be normal physiological fluctuations, or it may be caused by sepsis, upper respiratory tract infections and other diseases. 1. Physiological fluctuations: children’s body temperature is usually between 36 and 37 ℃, and the general temperature fluctuation is between 0.5 and 1 ℃, which does not require special treatment. During the daytime, the child’s body temperature will increase with time, and at night when he/she goes to bed, the body temperature will drop. 2. Sepsis: There are many reasons for septic patients to have fever, mainly because of the irregularity of the condition. For example, when they get up in the morning, the body temperature in some of them will drop, and the virus will suddenly break out, which will cause fever. 3. Upper respiratory tract infection: recurrent episodes of low fever caused by upper respiratory tract infection are mainly due to inflammation that is not completely eliminated, bacterial infection and so on. The phenomenon of sudden high and low body temperatures can occur. If the symptoms of the 8-year-old boy’s temperature fluctuating between high and low in the past two days are still not relieved after life adjustments, it is recommended to seek medical treatment in a timely manner.