Laryngeal cleft（LC）is rare congenital abnormal malformation. It is considered to be developmental anomalies due to failure of the fusion of the tracheoesophageal septum from fourth to eight embryonic weeks. LC have a number of airway symptom including aspiration and recurrent pneumonia.We herein experienced that a cause of arytenoid mucosal edema due to LC. This case was a 3-year-old girl. Her chief complaint was stridor and dyspnea. We observed her arytenoid mucosal edema and motion, such as the pendulum motion using a laryngeal endoscope. We considered that the potential causes of the arytenoid mucosal edema were allergy, laryngopharyngeal reflect disease（LPRD）and laryngomalacia. However, the arytenoid mucosal edema persisted after surgery. During the 4th operation, we noticed a LC. The patient currently does not have increased mucosal swelling, and is not suffering from aspiration and stridor.Type I LCs are largely undiagnosed in children. The diagnosis and management of LC is often delayed because it is difficult to diagnose LC. The diagnosis of LC must be made with the laryngoscope.
