A case of disseminated mycosis with encephalitis unobserved in life is reported. A mycosis infection ought always be taken into consideration every time that a clinical impression of encephalitis, meningitis or cerebral abcess is reached. Criptococcosis, Histoplasmosis and Candidiasis may present as a meningitis, which the Nocardiasis and the Cladosporosis may appear as an intracranial abscess in the absence of significant lesions of other organs. Many deep mycosis prove to have characteristic lesions in other organs before affecting the Central Nervous System. Development therefore of neurological symptoms ought to make one think of a dissemination at CNS level. Finally Candidosis and Aspergillosis ought to be suspected in all cases of progressive general weakeness after an illness especially when treated with antibiotics, citotoxis drugs, or hormonal steroids. In many cases the neurological lesions represant a manifestation of terminal type in a subject with many more lesions than one would suspect at first.