ObjectiveTo evaluate the efficiency and clinical outcomes of endoscopic thoracic sympathectomy (ETS) with flexible thoracoscopy under local anesthesia with monitored anesthesia care in primary palmar hyperhidrosis. MethodsFrom March 2011 to March 2013, we performed ETS with flexible thoracoscopy under local anesthesia with monitored anesthesia in 23 patients with primary palmar hyperhidrosis (PH), including 10 males and 13 females with their age of 25.6±7.2 years (range, 17-32 years). T3 sympathectomy was performed with flexible endoscopy under local anesthesia with monitored anesthesia care. All patients were followed up until May 2014. ResultsDuring surgery, the vital signs of the patients remained stable. Operation time was 30-40 minites. The symptom of PH disappeared right in the surgery. All patients were discharged from the hospital on the 2nd postoperative day. One patient received unilateral sympathectomy because of pleural adhesion. Other 22 patients received follow-up to May 2014 and no reoccurrence was reported. ConclusionETS with flexible thoracoscopy under local anesthesia with monitored anesthesia is a safe, microinvasive and effective method.