Yersiniosis is an acute or chronic zoonosis caused by rods belonging to species Y. enterocolitica and Y. pseudotuberculosis. The natural reservoirs of these rods are domestic and wild living animals. Pathogens are transmitted to host by contaminated food, water, and soil. The clinical manifestations of yersiniosis are variable from mild diarrhoeas to serious pathological organic lesions. The diagnosis of yersiniosis is often possible only on the results of the bacteriological or serological examinations because of lack of typical clinical manifestations. The antibiotic treatment is necessary in case of yersiniosis involving enterocolitis, septicemia, and organic lesions.