Sphenoid sinus mucoceles are pseudocystic expansile slow-growing processes that arise within the sphenoid sinus. A dynamic process of bone resorption and erosion results in a pseudo-tumoral development. Clinical features and potential risks are related to mass effect with compression of the optic nerves and intracranial extension of the process. CT and MRI allow diagnosis and distinguish mucoceles from skull base tumors or inflammatory diseases. Endonasal endoscopic approach is adapted to the treatment of sphenoid mucoceles and allows marsupialization of the mucoceles.