In the paper issues related to the occurrence of human pathogenic bacteria Listeria monocytogenes were described. First, the properties of that microorganism were characterized and the threats relevant to its presence in food were emphasized. In the further sections of the paper the attention was paid to the need for evaluation of effective methods to inactivate Listeria and therefore the possibility of the practical use of class IIa bacteriocins from lactic acid bacteria. The role played by the class IIa bacteriocins of lactic acid bacteria in the protection of food products against Listeria and as a consequence in listeriosis prevention was detailed. Other practical application of biological activity revealed by this class of bacteriocins were also highlighted.