Acute fulminant invasive fungal sinusitis is most commonly found in immunocompromised patients with conditions such as diabetes mellitus, malignancies and acquired immune deficiency syndrome. The most common pathogens are Aspergillus and Mucoraceae and the sinus most frequently involved is the maxillary sinus. Fever, rhinorrhea, facial pain, headache, and diplopia are common presenting symptoms. Complications of this infection include intracranial and / or intraorbital spread of the infection; the prognosis is poor. Here, a rare case of acute fulminant invasive fungal sinusitis with cavernous sinus syndrome is reported.