Crohn’s disease and terminal ileitis are mostly distinguished from each other by etiology, endoscopy, laboratory tests and imaging tests. 1. Etiology: Crohn’s disease is a chronic inflammatory granulomatous disease of the digestive tract of unknown etiology, mostly related to the environment, genetics, immunity and other factors, in addition to occurring in the ileocecal terminus, can also involve the neighboring colon. Terminal ileitis belongs to the category of enteritis, mostly due to the inflammatory reaction caused by pathogens infecting the intestines. 2. Endoscopy: Crohn’s disease of the intestinal mucosa is mostly ulcerative lesions, segmental or jumping distribution, the ulcers are mostly longitudinal distribution, there are typical non-caseous granulomas, tissue biopsy pathology can be observed in the mucosal tissues of fissure-like ulcers, nodular disease-like granulomas changes. Endoscopic mucosa of terminal ileitis generally shows inflammatory changes such as congestion and edema, erosion and bleeding. 3. Laboratory tests: Crohn’s disease fecal examination of occult blood test can be positive, usually will not find the pathogen, some patients blood test can appear autoantibody positive. Patients with terminal ileitis may find pathogens in fecal examination, and serum related pathogen antigen or antibody examination may be positive. 4. Imaging examination: Crohn’s disease can involve the whole gastrointestinal tract, in the small intestine is mostly jumping distribution, do small bowel CT imaging can identify whether the intestinal ulcer is confined to the terminal ileum. Patients who suspect Crohn’s or terminal ileitis are advised to seek timely medical attention, improve relevant examinations under the guidance of the doctor to identify the disease, and actively receive treatment to avoid delaying the condition.