Molds are vegetable microorganisms, which differ from dermatophytes sensitive to griseofulvin, and from yeasts, which do not form aerial mycelium. Most of the molds, phytopathogenic or which live from dead organic substances, are apathogenic to humans. Only a couple of dozen species can parasitize on the skin, usually together with dermatophytes or yeasts. Onychomycoses with molds appear mostly in elderly people, and fungus affections of external auditory passage in seborrheic eczema of the ear. The hair can be infected by Piedraia hortae, resulting in hard black nodules. After the identification of molds on the skin, criticism is necessary, since in more than 95% of the cases they are accidental germs. Several cultures and microscopic tests are necessary to assure the diagnosis. Broad-spectrum antimycotics is the predominant choice for treatment, but also amphotericin B, nystatin and pimaricin.