There is no pain sensation during anal fissure surgery, and the postoperative pain is mild and tolerable. I. Before the anal fissure surgery, a clean enema is needed to empty the rectum and no more bowel movements for 3 days after the surgery to avoid short postoperative time and anal pain during bowel movement and effectively relieve the patient’s fear of bowel movement; II. During the anal fissure surgery, a combination of hard and lumbar anesthesia or sacral canal anesthesia is taken, the surgical site is fully anesthetized and the whole surgical procedure is painless; III. The pain is very mild for 7 days after surgery; iv. The patient can ask the anesthesiologist to bring an analgesic pump during the anal fissure surgery to effectively relieve the pain.