Spindle cell carcinoma (SpCC) is a rare variant of squamous cell carcinoma (SCC). SpCC of sinonasal origin is relatively rare and more aggressive than normal SCC. It most commonly involves the maxillary sinus, and rarely the sphenoid sinus. The present study reports a case of sphenoid sinus SpCC presenting with bilateral visual loss. Following endoscopic sinus decompression surgery, the patient was referred to the Oncology Department for a staging workup, and subsequently received concurrent chemoradiotherapy; however, the vision of the patient was not recovered, despite treatment. To the best of our knowledge, this is the first reported case of synchronous inverted papilloma of the sphenoid sinus and SpCC presenting with optic nerve compression.