Blood in the buttocks for days on end may be caused by hemorrhoids, anal fissure, anal fistula, rectal polyps, rectal cancer and other conditions. 1. hemorrhoids: general internal hemorrhoids patients will appear hemorrhoids prolapse, bleeding and other symptoms, and the blood is bright red, more than the end of defecation will cover the surface of the stool, but also can be into the drops down, the severe cases can also be a jet of bleeding. If the external hemorrhoids are also prone to the phenomenon of bleeding, can be manifested as the buttocks for several days in a row with blood. 2. Anal fissure: the pathogenesis is not completely clear, mostly considered with the narrowing of the anal canal, reduced blood supply, infection and other factors, and anal trauma, inflammatory bowel disease, intestinal tuberculosis, female labor and delivery, etc. can be induced anal fissure. Patients often have symptoms such as pain, blood in stool, or blood in the buttocks for several days in a row. Some patients can also be accompanied by constipation, itching and other phenomena. 3. Anal fistula: usually due to rectal perianal abscess, can also be secondary to the infection caused by surgery, but also with bad habits, bad eating habits and other factors. Patients often appear to be anal fistula external mouth continuous or intermittent outflow of a small amount of purulent, bloody, mucous secretion. Some patients can also be accompanied by pain, itching, fistula defecation or exhaust. 4. Rectal polyps: Rectal polyps are caused by genetic factors, chronic inflammatory stimulation, gene mutation, etc. The main symptoms of patients are blood or bleeding in stool, change of bowel habits, abdominal pain. Therefore, patients will have blood in buttocks for several days in a row. 5. Rectal cancer: Most of the early rectal cancers are asymptomatic; when rectal cancer grows to a certain degree, there are changes in bowel habit, bloody stool, pus-blood stool, urgency, constipation, diarrhea, etc.; the stool gradually becomes thin, and in the late stage, there are obstruction of defecation, emaciation and even malignant disease. The situation of having blood in the buttocks for several days in a row can occur. It is recommended that patients with blood in the buttocks for several consecutive days should consult the hospital as soon as possible for standardized examination and treatment.