Viedo-assisted thoracoscopic surgery(VATS) have became popular in recent years. There is no golden rule of postoperative analgesia for VATS. Compared with lobectomy, wedge resection preserves better pulmonary function and is suitable for elder patients and patients who could not afford to have lobectomy. In addition to surgery time、recovery time and hospital stay, wound incisions and organization damages are different,too. Will patients also have different response to pain control after these two surgery? The retrospective study is to compared the differences of postoperative pain management between VATS lobectomy and wedge resection.