The symptoms of pain in the buttocks of the stool may have the following causes: 1, anal fissure, anal fissure caused by the pain in the buttocks of the stool is generally periodic, generally due to fecal stimulation of the anus, ulcer fissure expansion. The pain is mainly burning or cutting pain, which will last for a few minutes after defecation, but in severe cases, the pain will last for several hours. 2, anal sinusitis, the pain is caused by the pressure of feces on the anal sinus during defecation, and the pain will be stronger if the sphincter is stimulated, and there is also sticky secretion in the stool, which smells especially bad. 3, rectal cancer, there is no obvious pain in the early stage of rectal cancer, but with the development of the disease, the mass will gradually become more painful. However, with the development of the disease, the lump will gradually increase and ulcerate, and the anal area will have the feeling of swelling and pain. The stool will change in nature, and you will feel pain when you have a bowel movement, and you will also have abdominal pain and weight loss.