Generally, the symptoms of fever, vomiting and diarrhea in children are mainly caused by the following reasons. First of all, due to children suffering from acute gastroenteritis caused by symptoms, after the occurrence of acute gastroenteritis, especially bacterial gastroenteritis, due to bacterial invasion will cause children to appear gastrointestinal inflammation, which causes vomiting, diarrhea and fever, abdominal pain and a series of symptoms, can be timely anti-infective treatment, such as the application of cephalexin and so on. Secondly, due to children suffering from food poisoning caused by symptoms, eating not too clean food, can cause food poisoning, which will also cause fever, vomiting and diarrhea, need to timely anti-infectious and replenish fluids and electrolytes and other treatments.