Iatrogenic chylothorax is an uncommon thoracic duct injury, but well-known and serious complication after thoracic surgeries. Recently, video-assisted thoracoscopic surgery has been applied in the management of postoperative chylothorax and could be indicated earlier. We report herein a case of postoperative chylothorax managed successfully by early thoracoscopic direct suture repair of the site of chylous leak that developed after the thoracoscopic resection of mediastinal mass and surrounding fat with ectopic thymus in a patient with persistent myasthenia gravis with non-Hodgkin lymphoma.