Tummy fever when fever occurs may be caused by five reasons: First, fever will cause the temperature of the whole body to rise, and the temperature of the stomach will also rise. Second, fever is caused by viral infection, the virus reaches the gastrointestinal tract through blood circulation, which will cause the stomach temperature to rise. Third, when the body’s resistance is lowered during fever, the gastrointestinal flora is imbalanced, and a hot stomach occurs. Fourth, the fever makes the abdominal lymph nodes swollen, resulting in stomach fever. Fifth, if the patient has taken fever-reducing drugs or anti-inflammatory drugs, it may stimulate the gastrointestinal tract, causing abdominal discomfort and the appearance of stomach fever. It is best to go to the hospital for examination and early treatment.