Invasive fungal sinusitis (IFS) is more common in immunosuppressed patients but can also occur in immunocompetent hosts. While the non-invasive type of fungal sinusitis has usually a good prognosis, IFS is a potentially lethal condition.We report the case of a woman in her 60s presenting an isolated fungal infection by Aspergillus fumigatus of the right sphenoid sinus, causing extensive bone erosion of its walls and complicated by severe meningoencephalitis. She was healthy without any immunosuppressive conditions. Methods of diagnosis, multidisciplinary management, follow-up and outcomes are documented.Early-stage diagnosis of sphenoid sinus pathologies is often delayed because patients are usually asymptomatic. IFS of the sphenoid is more aggressive than other paranasal sinus and carries significant mortality. Early diagnosis and aggressive and multidisciplinary treatment are crucial to reduce sequels and improve patient's survival.