To the Editor:Mucormycosis and aspergillosis are opportunistic fungal infections that can lead to life-threatening complications.[1,2] Pulmonary actinomycosis is a rare infection which is commonly confused with other lung diseases.[3l Co-infection with these three pathogens in the same host is rare.Here,we report a unique case of a cavitary lesion with aspergillosis,mucormycosis,and actinomycosis co-infection.