Esophageal duplication cyst is very rare mediastinal tumor which is congenital lesion of the esophagus. Esophageal duplication cyst could be excised with video assisted thoracoscopic surgery(VATS) if it is relatively small, cystic lesion and not adhered severely to the surrounding tissues such as lung, trachea, bronchus, esophagus and pleura. We report a case of an esophageal duplication cyst which was located in the right thoracic cavity below carina and could be excised completely and repaired by interrupted suture with 3.0 black silk. The patient was discharged at 10 days after operation with good condition and has been in uneventful condition 2 months after operation.