The leakage of feces from the anus is mainly caused by the relaxation of the anal sphincter muscle, which cannot control defecation on its own. The main causes of anal sphincter relaxation include the following: 1. The symptoms of hemorrhoid prolapse and rectal prolapse caused by internal hemorrhoids can easily lead to fatigue and relaxation of the anal sphincter due to long-term stimulation, so that it cannot close rigorously after defecation and the phenomenon of fecal leakage occurs. 2. The phenomenon of fecal leakage caused by damage to the rectal ring connecting the anus and the sphincter, which is located in the lower mucosa of the rectum, is easily affected by external forces and has functional damage. 3, the leakage of feces caused by damage to their own nerve function, the human body through the nervous system to convey their consciousness, once the nervous system damage will lead to consciousness can not be conveyed in time, so that the anal sphincter can not be contracted or diastolic autonomously.