Fungi kingdom comprises ubiquitous forms of life with 1.5 billion years, mostly phytopathogenic and commensal for humans and animals. However, in the presence of impaired conditions fungi may cause disease by intoxicating, infecting or sensitizing with allergy. Different genera may be implicated as etiological agents for humans and animals, with Alternaria, Aspergillus, dermatophytes like Microsporum and Trichophyton, and Malassezia as the commonly implicated. Alternaria and Malassezia stand as the most commonly associated to either allergy or infection, immediately followed by Aspergillus, while dermatophytes are usually associated to ring worm skin infection. Research in veterinary field is not much but necessary.