Background & aimChromoblastomycosis is a chronic, progressive cutaneous and subcutaneous fungal infection clinically manifested by nodular, crusted and verrucose lesions appearing as a result of tissue proliferation around the site of traumatic inoculation of the exosaprophytic pigmented fungi. Up to now, little studies available documenting the presence of these organisms from environmental sources in Iran. Therefore, this study was aimed to investigate the presence of black fungi in the nature of Iran. Methods and materialsA total of 400 environmental samples including: air, soil, wood, plant matters, grain and organic debris were obtained from different areas (public places) belonging to Babol city of the Mazandaran province in north of Iran during one year. The grown dark colonies were then isolated and exposed to DNA extraction. All culture positive isolates were identified to the species level by DNA sequencing of ITS1–5.8S–ITS2 rDNA region. ResultsBased on morphological appearances, 79 strains of dematiaceous fungi including 13 genera and 23 species were isolated from 400 included samples. Cladosporium herbarum (17/79) was the most predominantly identified species, afterward Alternaria spp., Curvularia spp. and Ulocladium spp. in descending frequency isolated as well. Summer season was documented as the time of highest fungal isolation rate. ConclusionAlthough, all the environmental black fungi isolated strains from current study are regarded as nonpathogenic. However, the rise in the reports of chromoblastomycosis cases in both healthy and immunocompromised hosts, caused by these fungi that gain entrance through the skin by traumatic implantation of natural sources, all over the world is alarming.