Colonoscopy is an important method used clinically to check whether the intestine is accompanied by lesions, and generally based on whether the patient can be checked for intestinal obstruction by colonoscopy, an objective analysis should be made based on the specific parts of the patient’s intestinal obstruction. 1. If the patient is accompanied by colonic tumor lesions, with the growth of tumor cells causing intestinal lumen narrowing. Through colonoscopy, not only the specific site of intestinal obstruction can be clarified, but also the specific nature of intestinal lesion can be clarified through local biopsy under colonoscopy, which can provide important basis and plan for the next surgical treatment. 2. If the plane of intestinal obstruction is higher in jejunum or ileum, simply through colonoscopy, only the lesion of colon and rectum can be clarified, and the site and cause of small bowel obstruction cannot be found. For patients with small intestinal obstruction, clinically, it can be combined with abdominal enhancement CT examination to clarify the site and specific cause of obstruction, which can achieve better results.