There is blood on the paper after each stool. The common causes are: 1, some anal diseases: such as anal fissure, manifested as stool with fresh blood, after the stool accompanied by severe pain, knife cut-like pain, mostly seen in patients with dry stool, dry stool propped up the skin around the anus, there will be blood on the paper after stool, generally not much bleeding. 2, hemorrhoids: mostly seen in internal hemorrhoids. Patients with internal hemorrhoids are often accompanied by painless bleeding during defecation, or fresh blood attached to the surface of the stool, and the blood is mostly bright red in color. 3.Intestinal tumors or rectal polyps: This can also occur. If the patient is accompanied by weight loss, weakness, change in bowel habits, and the stool contains mucus and blood, consider that it may be a malignant tumor of the intestine. In case of blood in stool, one should go to the hospital for relevant examinations, such as colonoscopy, to clarify the cause and give symptomatic treatment.