Postoperative pain after anal fistula surgery must be experienced by every patient. The degree of postoperative pain is mainly related to the size of the trauma and the patient’s threshold for pain stimulation. Many patients have very severe pain after surgery, especially during the first bowel movement, and even have psychological shadows. To reduce the painful stimulation of defecation, the first step is to control the diet, generally 1-2 days after surgery into a liquid or semi-liquid diet, such as eating vegetables, fruits and other foods containing high fiber. In addition, the first bowel movement should be controlled 2-4 days after surgery. A warm water bath or local physiotherapy can be used to reduce the spastic pain caused by the stimulation of the anal sphincter after defecation. For individual patients with significant pain, intramuscular pain injections or oral painkillers can be used to relieve anal pain.