Background　The incidence of postoperative chronic pain is much higher than expected， seriously affecting the quality of patients′ life. Chronic pain after surgery is becoming increasingly prominent due to the lack of mechanism knowledge and effective treatments.　Objective　This review is to investigate the characteristics， risk factors and possible pathogenesis of postoperative chronic pain.　Content　Postoperative chronic pain is caused by multiple risk factors， which consist of preoperative factors， operative factors and postoperative factors. The development of chronic pain is a comprehensive process with various mechanisms， including nerve damage， nerve remodeling， and chronic inflammation.　Trend　Anesthesiologist should pay more attention to postoperative chronic pain， and try to seek its pathogenesis and explore its possible clinical treatments， such as preemptive analgesia.