Intermittent bleeding in stool may be caused by bowel cancer, or anal fissure, hemorrhoids and other reasons. 1. Bowel cancer: Colorectal cancer may lead to blood in stool, and there may also be pus and blood in stool, feeling of swelling in lower abdomen, anemia, emaciation, diarrhea or constipation and other symptoms. 2. Anal fissure: blood in stool is usually fresh and located on the surface of stool, which may be accompanied by severe pain during defecation and constipation. 3. Hemorrhoids: there may be no obvious clinical manifestations; blood in the stool may also occur, and even jet-like bleeding may occur. In addition, there will also be abnormal anal swelling or prolapse, if combined with infection, embedded or thromboembolism, there may be obvious pain symptoms. If there is blood in the stool, it is recommended that the patient go to the regular hospital in time to get a clear diagnosis and give reasonable treatment as soon as possible to avoid delaying the aggravation of the condition.