[Abstract] Objective To explore the causes and preventive measures of postoperative pain after PPH. Methods To retrospectively analyze the causes of postoperative pain in patients who underwent PPH from February 2008 to February 2013, and to summarize the methods of preventing and managing postoperative pain. Results Postoperative pain can be caused by pulling reaction, anesthesia, depth of purse-string suture and anal edema. According to the different causes of pain, we propose corresponding prevention and management methods to provide the basis for clinicians to carry out their work. Conclusion: Preoperative patient guidance, timely and effective preventive methods, and postoperative pain relief measures can reduce the patient’s pain and facilitate postoperative recovery. [Keywords] PPH; pain; treatment Anastomotic hemorrhoidal circumferential excision and stapling is a surgical method to treat internal hemorrhoids and mixed hemorrhoids by using anastomosis to circumferentially excise the mucous membrane of the lower end of the rectum, and PPH is based on the theory of anal cushion, which circumferentially excises the mucous membrane of the rectum that is controlled by the vegetative nerves, blocking the hemorrhoidal blood supply, suspending prolapsing anal cushion tissues, and decreasing the volume of hemorrhoids, PPH retains the normal function of anal cushion and does not affect its defecation reflex. Although PPH retains the normal function of the anal cushions, does not affect their defecation reflexes, and the pain is very mild, it is still impossible to avoid the occurrence of postoperative complications, especially postoperative pain. This is mainly related to the operator’s operating skills and experience, of which postoperative pain patients accounted for a considerable proportion, this paper analyzes the causes of postoperative pain after PPH and discusses its solution. 1, data and methods 1, 1 general information from February 2008 to February 2013, our hospital admitted 200 cases of clinically diagnosed mixed hemorrhoids hospitalized patients, of which 120 cases of men, 80 cases of women, age 32-84 years old, an average of 52 years old. PPH was performed under lumbar anesthesia, and the patients were lying down for 6 hours after surgery. Reason analysis 2.1 Small abdominal pain During surgery, when tightening the purse-string suture, tightening the anastomosis and striking the process is often accompanied by vagal reflex phenomenon due to pulling. In mild cases, it is manifested as lower abdominal pain, nausea, vomiting, irritability; in severe cases, there is a rapid decline in heart rate, blood pressure drop, and even neurogenic shock. 2,2 Anal pain: the position of the purse-string suture is low, the anastomotic nail and the anastomosis on the surface of the hemorrhoidal nucleus mucosal stimulation, anal spasm and the position of the anastomosis is low will lead to prolonged postoperative anal pain; expanding the anal device to expand the anus roughly, resulting in the inner sphincter tear; purse-string suture is too deep, injuring the rectal intrinsic muscular layer, the formation of submucosal hematoma in the anastomosis; anastomotic nail directly stimulate the somatic nerve fibers near the dentate line, causing anal pain; when defecating, anastomotic sutures are too deep, injuring the rectal intrinsic muscle layer, and anastomosis sub mucous hematoma formation; anastomosis nail directly stimulates the somatic nerve fibers near the dentate line, causing anal pain. The anastomotic nail directly stimulates the somatic nerve fibers near the dentate line, causing anal pain; the anastomosis is dilated and impacted during defecation. 3, treatment countermeasures 3, 1 preoperative treatment 30 min before the operation, intramuscular diazepam 10 mg, atropine 0, 5 mg, can reduce the patient’s nervousness and reduce gastrointestinal peristalsis. 3.1 Intraoperative treatment If the purse-string suture is placed in an area of 3-4 cm above the dentate line, postoperative pain can be significantly reduced. The purse string should not be too deep, and it is sufficient to reach the submucosal layer. The anus should be dilated only after the anesthesia has taken full effect and the anus is completely relaxed. If the anus is not completely relaxed, local anesthetics can be injected to achieve the relaxation effect. If the patient’s anus is small, sphincter relaxation can be performed before anal dilation. After circumcision, the anastomotic nail should be carefully inspected to make sure whether it is completely wrapped, and if it is exposed, it should be removed. 3.2 Postoperative treatment Patients should start to take medication to help defecation in the evening of the 2nd day after operation to help gastrointestinal peristalsis or soften the stool, so that the patient can exert less force when defecating, thus reducing the pain, and enema can be given when necessary. If the patient has pain after surgery, the following treatment measures can be taken: 1, oral or intramuscular injection of pain medication. For example, oral diclofenac sodium and other painkillers, such as the effect of the pain is more intense can be intramuscular pethidine hydrochloride 50 ~ 100 mg. 2, postoperative placement of analgesic pumps. 3, fumigation. Chinese medicine sitz bath refers to the medicine decoction or boiling water soaked, while hot fumigation, fumigation, after washing the affected area with the liquid treatment method. 4, Discussion In summary, PPH surgery has the characteristics of less postoperative pain and faster recovery compared with the traditional surgery, but some patients still feel pain, in order to reduce the postoperative pain, firstly, we should strictly grasp the indications for surgery, and only operate on the patients who really need the surgery, and should not blindly expand the scope of the surgery; secondly, we should improve the level of surgical operation, and reduce the injuries caused by surgical errors; again, we should improve the level of surgical operation and minimize the injuries caused by surgical errors; and thirdly, we should improve the level of surgical operation and minimize the injuries caused by surgical errors, in order to reduce the postoperative pain. Secondly, we should improve the level of surgical operation to reduce the damage caused by surgical errors; thirdly, we should adopt appropriate treatment measures in time to minimize the pain of patients who have pain after surgery.