With recent advances in medicine, fungal diseases are not only being better under stood, but are also becoming increasingly important in the management of patients with paranasal sinus disease. Fungal sinus diseases range from allergic fungal sinusitis to invasive and fulminant fungal sinusitis. Although patients often have some predisposing factor, such as local tissue hypoxia or massive fungal ++exposure, most patients are not immuno-compromised. Invasive fungal sinusitis may be treated with the traditional Caldwell-Luc surgical technique or with newer endoscopic procedures. Fulminant fungal sinusitis generally occurs in immuno-suppressed patients and requires aggressive surgical excision and debridement as well as systemic chemotherapy, usually amphotericin B. In this article we review fungal diseases of the paranasal sinuses and present four cases of paranasal fungal sinusitis.