Laryngeal web is extremely rare disease. Congenital laryngeal web is secondary to inadequate recanalization of the laryngeal lumen. Congenital laryngeal web account for about 5% of congenital anomalies of the larynx. About 75% occur at the glottis level, and the rest are supraglottic or subglottic. Acquired laryngeal web is caused by iatrogenic injuries, external neck trauma or chronic infection. Most webs present at birth or in the first few month of life. The severity of the web varies. Symptoms depend on the degree of larynx narrowing. Management depend on the degree and severity of stenosis, shape, and whether there are associated congenital anomalies. Mild case of stenosis are managed conservatively by watchful waiting and regular follow up. Only a few are severe enough to required airway support by intubation or tracheostomy and reconstructive repair. We report a case of an unknown etiologic supraglottic web in a 45-year-old woman. There are no symptoms which related to airway and voice. But sometimes, the patient had experienced dysphasia with recurrent aspiration. Therefore the web was found by chance, then we managed with an endoscopic dilation.