The incidence of fungal infection of the paranasal sinuses is increasing due to increasing use of antibiotics, steroid and chemotherapeutic agents. It is reported that Aspergillosis is the most common fungal infection among the fungi which involve the nasal cavity and paranasal sinuses. Recently, the authors experienced five cases of Aspergillosis in maxillary sinus diagnosed by operative findings and biopsy that were treated by the paranasal sinus operation under diagnosis of chronic maxillary sinusitis. We report these cases with review of literatures.