Abstract: Objective The present study was conducted to find out the situation of Yersinia enterocolitica carried by animals in Ji County, Tianjin City in order to prevent and control Yersinia enterocolitica infection well. Methods From May 2006 to June 2006, surveillance on the poultry and domestic animals (such as pigs, cows, sheep, and chickens) was developed in the whole county. Yersinia enterocolitica were isolated and cultured by the cold enrichment method. Results 4 strains of Yersinia enterocolitica were detected in the stool of pigs, among which it was identified by PCR that 3 stains had the 4 virulent genes, ail, ystA, yadA and virF, and also had the serogroup O:3 rfb gene, and 1 strain had the virulent gene, ystB. Conclusion The pig is one kind of the animal hosts of Yersinia enterocolitica, and the stool of pigs may become the source of the food pollution.