Nasal septal cyst is a rare complication seen after submucous resection of the nasal septum. A 25-year-old male patient presented with a complaint of nasal obstruction four years after submucous resection. Physical examination revealed a grey mass obstructing both nasal cavities and the nasal airway. Magnetic resonance imaging showed a nasal septal cyst filling the nasal cavity. Following aspiration of the cyst content, endoscopic examination was performed and perforation of the lower part of the nasal septum was noted. Under local anesthesia, superior, posterior, and anterior parts of the cyst and the left wall of the septum were endoscopically released and prepared to be used as a flap. It was sutured on the lower part of the septal perforation. No recurrence was seen during a follow-up of 18 months.