Tittle: Applying endoscopic thoracic sympathectomy in treatment of palmar hyperhydrosis. Introduction: Palmar hyperhydrosis is the common form of hyperhydrosis. Endoscopic thoracic sympathectomy is choiced to treat it. Objective: To evaluate the results and complications of endoscopic thoracic sympathectomy in treatment of palmar hyperhydrosis. Research method: prospective study. Results: + Immediate result after surgery: 100 percent both hands dried. + Later results (19 - 43 months): good and medium: 85,71 percent, recurrent and bad: 14,28 percent. + The rate of postoperative sweating cover: 71,42 percent (57,14 percent slight). + There is not serious complication. Conclusion :