The symptoms and bleeding sites of the onset of blood in stool and bloody stool are different, as follows: 1. There are more causes of bloody stool, the common ones are anal fissure, hemorrhoids, rectal cancer or rectal polyps. Bloody stools caused by rectal cancer or rectal polyps, which are easily attached to the surface of feces, are often caused by bleeding from the lower gastrointestinal tract, and the bloody stools are mainly bright red blood, which is easily found in the lower gastrointestinal tract. 2. Blood in stool is mostly bleeding from the gastrointestinal tract, and blood will be discharged from the anus, and the symptoms of blood in stool are manifested as paste-like, watery, thin with blood, formed or unformed bright red, dark red or black red blood, which will be discharged along with the stool. Blood in the stool may be caused by diseases of the upper or lower gastrointestinal tract, and the amount, speed and location of bleeding may vary.