Numbers and type of the cycloheximide-resistant part of the aerially transmitted mycoflora of Turin were studied. Samples from three areas characterized by differing human usage were taken in the first week of March. During each sampling, 12 m3 of air were aspirated, using an one-stage volumetric sieve sampler. Fifty-two mesophilic species and eight thermotolerant were isolated. Propagule load varied from 2.92 to 120.31 cfu m-3. The following species appear not to have been reported previously from air samples: Ascotricha bosei, Blastobotrys navarrensis, Cryptendoxyla hypophloia, Chrysosporium an. gymnoascus demonbreunii, Ophiostoma piceae, Penicillium vulpinum, Phialophora mustea, Rhinocladiella pedrosoi, Scopulariopsis croci, S. komngii and Sesquiallium candelabrum. A significant number of potential opportunistic pathogens was isolated.