Subcutaneous fistula that is low anal fistula, its main clinical manifestations are, anal fistula exudate increased, mainly purulent, bloody, mucus secretion, part of the infected people, can be accompanied by fever, fatigue, chills and other symptoms. Subcutaneous fistula occurs when the secretion increases, manifested as anal moisture, itching, can be accompanied by varying degrees of pain, serious ulcerated pus, very easy to cause infection; pus can not be discharged, will lead to perianal swelling, causing defecation difficulties. Subcutaneous fistula occurs, should be treated as soon as possible to avoid causing serious infection, commonly used therapeutic drugs are cephalosporin, metronidazole, etc., most people need surgery. Avoid smoking and alcohol. Diet management: light diet, avoid spicy diet, eat more vegetables and fruits.