The purpose of this study was to examine the efficiency to use by the thin thoracoscope for the palmar hyperhidrosis. General anesthesia with double lumen endotracheal intubation was used in all cases. A 2 mm incision made in the anterior axillary line in the third intercostal space. Pneumothorax was obtained by insufflation 1.5-2 L of CO2. A 2 mm endoscopic trocar was inserted through this incision, and a 2 mm, 0-degree scope (Autosuture, USA) was introduced. A second 2 mm trocar was inserted in the middle axillary line in the fourth intercostal space, through which a straight endoscopic seizer was introduced. The chain was dissected by electrocutting the white and gray rami and was incised over the second and third ribs. To avoid puemothorax, 8 F thoracic catheter was introduced through a guide wire which was inserted through a 2 mm trocar. The lung was expanded, and then the thoracic catheter was removed. We performed six sympathectomies on three female patients. All patients was satisfied of their results. This technique used by thin thoracoscope was cosmetic and a skin incision did not need to close too small.