Nine thermophilic genera and 17 species in addition to one variety of Aspergillus flavus, Malbranchea pulchella and Humicola grisea were collected from hair samples in Riyadh, Saudi Arabia at 45 degrees C. Fifty-one hair specimens of rabbit, sheep, camel and horse were examined for the presence of thermophilic fungi. The most frequent species were Aspergillus fumigatus, Aspergillus niger, Thermoascus aurantiacus and Malbranchea pulchella var. sulfurea. In low frequency, Aspergillus flavus, Aspergillus quadrilineatus, Paecilomyces variotii, Paecilomyces aerugineus, Mucor pusillus and Rhizopus stolonifer were also recovered. The hair samples tested in the present study were completely free from any keratinolytic fungi at 45 degrees C.