Osteomas are the most common benign tumors of the nose and paranasal sinuses. Their symptoms, which are nonspecific, occur as the result of a blocked nasal airflow or, in some rare cases, the involvement of nearby structures. Isolated sphenoid sinus osteomas are very rare, as only 20 cases have been previously reported in the literature. Most authors advise surgical treatment for symptomatic lesions. Surgical access to the sphenoid sinus has traditionally been a challenge for surgeons. We describe an endoscopic transnasal paraseptal resection of a sphenoid osteoma in a 35-year-old man. We also discuss surgical access and review the evolution of the surgical approaches to the sphenoid sinus.