Hemorrhoids are divided into internal, external and mixed hemorrhoids. The main symptom of internal hemorrhoids is bleeding during or after defecation, and if there is no combination of other colorectal diseases, there is no abnormality found in colonoscopy. Below the mucous membrane of the anal canal, there is a ring-like soft tissue structure called the anal cushion, which contains venous plexus, smooth muscle, connective tissue and so on. Prolonged constipation, fecal dryness and other factors can make the anal cushion tissue elasticity decline, congestion, hyperplasia, downward displacement and so on and then form internal hemorrhoids. As internal hemorrhoids are located above the dentate line of the anal canal and covered by mucous membrane tissue, they are easy to rupture and bleed when they are rubbed, thus internal hemorrhoids are mainly manifested as bleeding during or after bowel movements. Colonoscopy can observe the whole section of cecum, colon and rectum, which is important for checking various colorectal organic lesions. If the colonoscopy does not find obvious abnormalities can be excluded organic colorectal lesions. Hemorrhoids patients with blood in the stool, colonoscopy without abnormalities can basically exclude other colorectal diseases, so patients do not have to worry too much, follow the doctor’s orders for hemorrhoids to carry out the appropriate treatment.