The so-called “functional” gastrointestinal disease refers to a collection of chronic or recurrent gastrointestinal symptoms that cannot be explained by structural and biochemical abnormalities. After detailed physical examination and necessary auxiliary examinations, including routine blood, fecal, urine, sedimentation, liver function, kidney function, gastroscopy and colonoscopy are mandatory, and fecal bacterial culture, serum tumor markers, abdominal ultrasound, thyroid function measurement, gastroscopy and barium meal of the gastrointestinal tract are selected according to the condition, and those with a medical history of more than six months and no abnormalities in the above indicators are excluded. If there is no abnormality in the above indexes, the relevant organ is excluded.