The choice of CT or colonoscopy for intestinal disease examination should be based on the patient’s specific situation, and only the most suitable method is the best examination method. Commonly used tests for intestinal diseases include colonoscopy, small enteroscopy, CT, MRI, ultrasound endoscopy, capsule endoscopy, gastrointestinal angiography, etc., each of which has its own advantages and disadvantages and scope of application. CT is indispensable for the diagnosis of intestinal lesions and lesions that need to be localized, and it can show lesions within the intestinal wall and extra-luminal lesions, clarify whether there are metastases or not, and have a certain significance for the staging of tumors, but it is used with caution in CT-enhanced examination for patients with hepatic and renal insufficiency. Colonoscopy can not only visualize mucosal lesions in the intestines, but also be able to take biopsies and carry out hemostatic treatment, but it should be contraindicated for patients who are intolerant to gastroenteroscopy or have contraindications. It is recommended to choose the appropriate examination method under the guidance of the doctor, so as to timely detect lesions and actively treat them to avoid adverse effects.