Meningitis caused by Listeria monocytogenes is a rare affection: it develops from close contagion as professional illness (veterinarians, butchers) or in newborns by infected mothers; in indirect way for ingestion of contaminated food in subjects at high risk: elderly, immunosuppressed patients, alcoholics, diabetics. Clinically it is not diversified from the other bacterial meningitises. In this paper we present a case of Listeria monocytogenes meningitis in an adult female, without a sure occasion of infection and in absence of the factors of typical risk.