Abstract: The prevalence of invasive filamentous fungal infections has been rising with the increase of high-risk population. Although Aspergillus fumigatus remains the most frequent cause of these infections, nonfumigatus Aspergillus species such as Aspergillus terreus and non-Aspergillus filamentous fungi such as Fusarium species, Scedosporium species and Zygomycetes have emerged as important pathogens. These fungal species are inherently resistant or less susceptible to amphotericin B or other antifungal drugs, and often cause a high mortality in patients. The epidemiology of invasive filamentous fungal infections is reviewed here to emphasize the clinical importance of early pathogenic diagnosis and selection of active antifungal agents.