Blood on the surface of the end of the last section of stool may be caused by hemorrhoids, anal fissure, rectal polyps and other reasons. 1. Hemorrhoids: the disease can lead to the patient’s anus and rectal area swelling, in the process of defecation, due to the hard and dry stool, is likely to lead to hemorrhoidal nuclei rupture bleeding, which may cause the last section of the last section of the stool on the surface of the blood, may also be accompanied by anal swelling, pain and other symptoms. 2. Anal fissure: it is considered that it may be caused by trauma, ulcerative colitis, Crohn’s disease and other reasons, resulting in rupture of the skin of the anal canal below the dentate line, especially during defecation, which is easy to cause mechanical trauma, which will cause blood on the surface of the last section of the end of the stool, and it may be accompanied by constipation, perianal pain and other symptoms. 3. Rectal polyps: usually by the rectal mucosa to the intestinal lumen protruding hyperplasia, in the patient defecation, easy to form friction stimulation of rectal polyps, may cause polyp rupture bleeding, resulting in the last section of the last section of the stool on the surface of the blood, may also be accompanied by abdominal pain, diarrhea and other symptoms. Blood on the surface of the last part of the stool may also be caused by other reasons. It is recommended to consult a doctor as soon as possible to diagnose the causative factors through further relevant examinations, and then under the guidance of the doctor for treatment.