While invasive pulmonary aspergillosis usually occurs in immunocompromised hosts, it has been described after influenza virus infection in healthy individuals. The first case was a 76-year-old previously healthy woman admitted because of chest pain, cough, sputum, fever, and a chest radiograph abnormality. A transbronchial biopsy specimen showed fungal hyphae. Amphotericin B (AMPH) and Itraconazole (ITCZ) were given, and she improved gradually. A viral test showed a titre of 1/128 to influenza A. Case 2 was a 72-year-old previously healthy man admitted because of cough, fever, chest pain and a consolidation and cavitation on the chest radiograph. Antibiotics were ineffective. Cavitation with a halo sign appeared on the contralateral lung. Because his daughter was infected with Influenza B, we suspected he had been infected with IPA following influenza infection. AMPH and ITCZ and Micafungin sodium were given. His respiratory failure worsened, and on the tenth hospital day he required artificial ventilation; his condition improved gradually, (extubation after 40 days.) A viral test showed a titre of 1/128 to influenza B. IPA must be considered for the differential diagnosis of complications of influenza virus infection.