Every time the blood in the stool will hurt, consider that may be caused by anal fissure or hemorrhoids. 1. Anal fissure: clinical manifestations are pain, constipation and bleeding. The pain is severe, manifested as pain during defecation and pain after defecation. Anal fissure is the formation of small ulcers after cracking the skin layer of the anal canal below the dentate line. The triad of anal fissure presents as anal fissure, anterior hemorrhoids, and anal papillary hypertrophy. A small amount of blood or drops of fresh blood can be seen on the surface of the feces during defecation. 2. Hemorrhoids: clinical manifestations are bleeding and prolapse. Fresh blood after intermittent bowel movement is a common symptom. If accompanied by inflammation or acute thrombosis, can be accompanied by anal pain. Hemorrhoids are divided into internal hemorrhoids, external hemorrhoids, and mixed hemorrhoids. Mixed hemorrhoids are more likely to be painful every time there is blood in the stool. Whenever the symptoms of blood in stool and pain occur at the same time, there may also be other perianal diseases, such as perianal warts. If there is blood in the stool with pain, you should go to the hospital in a timely manner to get a clear diagnosis and follow the doctor’s instructions for treatment.