A polymerase chain reaction (PCR) assay was developed for detection ofpathogenic, virulent strains of Yersinia enterocolitica. By using both virulence loci virFand ail as markers for pathogenicity, detection of species with a virulence factor present waspossible. DNA preparation in the presence of hexadecyl trimethy ammonium bromide(CTAB) was followed by two 44 cycle amplification reactions, one for each of themarkers. As few as 102Y. enterocolitica cells were detected in ground pork in thepresence of 105–106bacteria of other species. The described PCR assay providesa sensitive robust assay for the detection of virulent Y. enterocolitica in food.