A submucosal lymphatic cyst is a thin-walled cyst, lined by flattened lymphatic endothelium, containing thin serous fluid. It rarely causes clinical symptoms, and it is incidentally discovered during fiberoptic panendoscopy or radiologic study in most cases. It is an extremely rare benign tumor of the stomach; however, a submucosal lymphatic cyst should be considered if a pliable and benign submucosal lesion is detected during fiberoptic panendoscopy. We report a case of submucosal lymphatic cyst of the stomach which showed a typical clinical picture. This report is the first case of submucosal lymphatic cyst of the stomach in Korea to the best of our knowledge.