There are several causes of men’s belly pain: 1, urinary tract infections and urinary stones, especially bladder infections and bladder stones, can cause pain in the belly, which may be accompanied by blood in the eyes and perineal radiating pain. 2, rectal tumors, rectal tumors may also cause pain in the belly, which may be accompanied by shortness of breath and mucous blood stool. 3, it may be constipation, constipation, which is manifested by difficulty in defecation and dry stool, may also manifest as pain in the belly. The most common cause of pain is the pain in the scrotum and testicles.