Fever with vomiting and diarrhea may be caused by acute gastroenteritis, gastrointestinal colds, ulcerative colitis, acute hemorrhagic necrotizing enterocolitis and other causes. 1. Acute gastroenteritis: Acute gastroenteritis may be caused by bacterial infection, viral infection, parasitic infection and so on. Patients will have abdominal pain, nausea and vomiting, abdominal pain and other manifestations, and some patients will also have low-grade fever, loss of appetite and other symptoms. Therefore, patients with acute gastroenteritis will manifest as fever, vomiting and diarrhea. 2. Gastrointestinal cold: Gastrointestinal cold may be caused by respiratory syncytial virus, rhinovirus, adenovirus and other pathogens. Patients will have nausea and vomiting, diarrhea, fever, nasal congestion, headache, abdominal distension and other symptoms. If the patient has a gastrointestinal cold, there will be fever and vomiting and diarrhea. 3. Ulcerative colitis: the cause of ulcerative colitis is not yet clear, and it is considered to be related to genetics, intestinal microecological abnormalities, immune factors and so on. Patients will manifest abdominal pain, abdominal pain (discomfort in the lower abdomen, want to defecate, after defecation, there is a feeling of incomplete defecation), recurrent diarrhea, nausea and vomiting, loss of appetite, and some patients will have fever in severe cases. 4. Acute hemorrhagic necrotizing enterocolitis: the cause of acute hemorrhagic necrotizing enterocolitis is still unclear, and it is considered to be related to C aerogenes infection. Patients will have abdominal pain, diarrhea, blood in the stool, nausea and vomiting, fever and other manifestations, so that patients will have fever, vomiting and diarrhea. It is recommended that when patients have fever, vomiting and diarrhea, they need to consult a doctor in time, and the doctor will treat them after clarifying the cause of the disease.