Maxillary sinus mucocele is very rare in the Para nasal sinuses and sinus surgery e.g. Caldwell-luk surgery is the most common its etiology and other causes are congenital ,mucosal retention , inflammatory , infectious and post traumatic.

          This study reports one case maxillary sinus mucocele with expansion to nasal cavity in 55 years old man that was undergone endoscopic sinus surgery and then fallowed up for 9months that middle meatal antrostomy was patent and patient reported resolution of symptoms and hadn’t recurrence.