Abstract: Objective To understand distribution of Yersinia enterocolitica and their etiology in selected plague foci in Yunnan province. Methods The mouse's cecum were collected in Jianchuan and Lianghe counties,Y. enterocolitica were detected by using colony PCR, the strains' biochemical identification and virulence genes detection were conducted. Results A total of 35 strains of Y. enterocolitica were isolated from 915 specimens (3.83%), only 1 strain was pathogenic. All the 35 strains belonged to biological type 1A. The pathogenic strain belonged to type 1A/O:9, and it's virulence genes included ail+, ystA-, ystB-, yadA-, virF-, rbfc-. The non-pathogenic strains belonged to serotype 1A/O:5, O:8 and were unspecified, and their virulence genes included ail-, ystA-, ystB+, yadA-, virF-, rbfc-. Conclusion Y. enterocolitica circulated in plague focus in Jianchuan, the serotypes of the strains varied and no typical virulence gene was detected in the pathogenic strain isolated. No Y. enterocolitica strain was detected in plague focus in Lianghe.