A case of necrotizing pneumonia secondary to Fusobacterium necrophorum is reported. This anaerobic infection commonly originates in the upper respiratory tract and is often accompanied by multiple system disease due to hematogenous seeding. When the lungs are involved, diffuse necrotizing pneumonia with pleural effusions and cavitation results. The course is prolonged, and the diagnosis is frequently delayed. With appropriate antibiotics, the prognosis is good.