Objectives: This study was applied to investigate the incidence of Yersinia enterocolitica in raw farm and market milk and studying the quality drawbacks which might happen in milk as a result of its existence. Design: Observation study. Samples:Onehundred raw milk samples. Procedures: Fifty bulk tank milk (BTM), 25 individual milk & 25 market milk samples were collected from various dairy farms and supermarkets in Dakahlia Governorate, Egypt. The quality assessment of the samples began with evaluating the milk physical characteristics including color, odor, pH and the titratable acidity that reflected the hygienic quality of milk production on farm levels. Then the samples were directed for biochemical and microbiological examination with subsequent PCR approach. Results: The range of titratable acidity started from 0.11 – 0.20 % lactic acid with a mean value of 0.15 ± 0.004. While for microbiological examination of the samples by using the conventional methods of cultivation on (CIN) agar medium, 33 presumptive Yersinia isolates were recovered and intended for biochemical tests among which 5 out of these latter isolates were confirmed as Y. enterocolitica by applying PCR, through detecting the presence of 16srRNA gene. Also, this study evaluates not only the public health of consumers concerning the titratable acidity of the examined samples, but also the economic importance of these retailed samples in supermarkets; as Y. enterocolitica could be transmitted through the consumption of raw milk.                                                                                                                                                                                                                                                                                            Conclusion and Clinical Relevance:The Y. enterocolitica incidence was 29% in the examined raw farm and market milk samples.