Fungus infections involving the nasal and paranasal cavities appear to be ralatively rare in occurrence, especially so with that of aspergillosis. However, with the advent of therapy with antibiotics, steroid hormones, and anticancerous agents, the incidence of such infection seems to have increased. The authors are reporting the cases of aspergillosis of maxillary sinuses with a reviews of literatures. Patients complained of nasal obstruction, headache and postnasal dripping for several years. Roentgenograms of paranasal sinuses revealed moderate cloudiness in maxillary sinuses, and there was no bony destruction. Operative findings included caseous necrotic mass of tissue in maxillary sinuses, which was biopsied and proved essentially mass of fungi, showing numerous distinctly septated, branching hyphae on the papanicolaou stain and hematoxylin-eosin paraffin sections. Pertinent aspects of clinical and pathological differential diagnosis between aspergillosis and mucormycosis are described.