Incidence of Listeria spp., in frozen poultry carcasses at supermarket in northwest Bogotá Listeria spp. it is a bacterial gene that contaminates foods of animal origin including poultry, where it can remain viable during the chains of production and distribution. In this work, 91 samples of chicken carcasses were analyzed; they were obtained in a distributor in northwest Bogota. The samples were taken in a period of 9 weeks and processed shortly thereafter. From the 91 carcasses, 40 (43.95%) were positive for Listeria spp. The presence of this microorganism can be associated to deficiencies in the systems of cleaning technology in the poultry factory and/or contamination with utensils during cut-up.