Chronic anal fissure generally can not use salt water sitz bath. Chronic anal fissure is mainly related to long-term dry stool and defecation difficulties, patients often have longitudinal ulcers in the anal canal fissure, with saline bath is likely to aggravate the pain and discomfort in the anus, but also may lead to prolonged local recovery time. Therefore, anal fissure patients should not blindly use salt water sitz bath. Chronic anal fissure patients can use 1:5000 potassium permanganate solution or warm water sitz bath under the guidance of the doctor, to promote local blood circulation, anti-inflammatory swelling, and promote the healing of anal fissure wounds, but also under the guidance of the doctor, the external use of compound keratine cream and other medications, the drug has a haemostatic, analgesic, and mucosal repair effect, can promote the recovery of local wounds. Chronic anal fissure patients also need to improve the diet, usually pay attention to eat more fruits and vegetables, to maintain smooth stool, to avoid dry stool, constipation on the anal fissure wound caused by repeated stimulation.