I. Our consensus opinion on the diagnostic criteria of Crohn’s disease includes the following five aspects: 1. clinical manifestations. 2, imaging examination. 3, colonoscopy. 4, mucosal histological examination. 5, resection specimen. How to make the diagnosis of Crohn’s disease according to the consensus criteria? The consensus opinion points out that the diagnosis should be made based on a comprehensive analysis of clinical manifestations and multiple ancillary examinations. Therefore, when a patient has persistent or recurrent abdominal pain and diarrhea, it is recommended that after excluding chronic intestinal infections such as intestinal tuberculosis, amoebic dysentery, Yersinia pestis infection, intestinal lymphoma, diverticulitis, ischemic enteritis, leukoaraiosis and ulcerative nodes, the diagnosis can be made according to the following criteria: ① those with the above clinical manifestations are clinically suspected, and further examination should be arranged. ②With the above-mentioned characteristics of items 1, 2 and 3, the clinical diagnosis of the disease can be proposed. ③If the 4th or 5th pathological examination is added, and non-caseous granuloma with one other typical manifestation or without granuloma but with the above three typical histological changes is found, the diagnosis can be confirmed, that is, the clinical diagnosis is emphasized and the pathological diagnosis is confirmed. ④After excluding the above diseases, the diagnosis can also be made according to the six diagnostic points recommended by the World Health Organization (WHO) combining clinical, radiographic, endoscopic and pathological manifestations, but the application of this diagnostic criterion is limited because these conditions are difficult to meet clinically. ⑤ When the diagnosis is difficult to be confirmed in initial cases, clinical and imaging or endoscopic and biopsy changes, the patient should be followed up and observed for 3-6 months. If confused with intestinal tuberculosis, diagnostic treatment should be given as intestinal tuberculosis for 4-8 weeks to see what happens later.