Under normal circumstances, no matter ordinary colonoscopy or painless colonoscopy, under normal circumstances, it will not cause perforation of the intestinal tract.1, the intestinal wall of the intestinal tract is divided into multiple layers, and the toughness of this layer of smooth muscle is relatively strong, and it is difficult to penetrate the intestinal wall under normal operation.2, the colonoscopy is composed of tubes, which have a soft wall, and it will not cause intestinal tract damage under normal circumstances. Of course, there are some special cases, such as malignant tumors, ulcers, etc., which cause the intestinal wall to be relatively thin, then perforation of the intestinal tract may occur. However, in this case, the operator will usually find it, and the operation will be more gentle, if it is not possible to pass, usually will not be examined, but just take the pathology.