Fungal infections involving the nasal and paranasal sinuses appear to be relatively rare in occurrence, but it is increasing tendency with the advent of therapy with antibiotics, steroid hormons and anticancerous agents. The symptoms and signs of this disease may duplicate early malignancy of this area and chronic suppurative maxillary sinusitis, and it should be suspected when the sinusitis is refractory to antibiotic and repeated antral irrigation. The authors recently experienced the one case of aspergillosis of maxillary sinus which was treated with modified Denker's operation.