Objective: To present a case of alveolar rhabdomyosarcoma (ARMS), unusual in its presentation as orbit apex-carvernous sinus apex syndrome and also its origin from the sphenoid sinus.Methods: A 23-year-old male with a right false eye, who presented to an outside hospital and was misdiagnosed as optic neuritis, complained of relapse-remitting course of visual loss with taking glucocorticoids and diffuculty with limited ocular motility in his left eye for 4 months.His symptoms and signs were consistent with orbital apex syndrome, probably due to multiple sclerosis-associated optic neuritis (MS-ON).