An anterior clinoid mucocele, known to be extremely rare, can lead to visual complications due to its proximity to the optic nerve. We report a patient who developed visual disturbance due to an anterior clinoid mucocele. Interestingly, the anterior clinoid mucocele coexisted with a sphenoid sinus mucocele. When an anterior clinoid mucocele coexists with a sphenoid sinus mucocele, more deliberate diagnostic and therapeutic approaches must be considered according to our first experience