|The subject of this study was to test the influence of regular consumption of kefir beverage (Danone company) comprising probiotic bacterial strains (Bifidobacterium animalis 108 CFU/g–1, Lactococcus lactis, Streptococcus thermophilus, Lactobacillus sp., Leuconostoc mesenteroides…), inulin, and yeasts (Debaryomyces hansenii, Pichia fermentas, Torulopsis holmii) on the incidence of Enterococcus faecalis in the human stool. Five hundred women (age 18–55), who had suffered from various forms of indigestion, were selected by questionnaires. We then selected from this group 50 volunteers who consumed a 200 ml kefir beverage regularly, each evening, after dinner. Their stool samples were taken before the research period started, and after two weeks of kefir beverage consumption. The women also filled in the questionnaire about their subjective feeling (alimentary function) after 14 days of kefir beverage consumption. The microbiological cultivation was carried out on a special medium Slanetz Bartley – pick-up Enterococcus faecalis (M 612 HiMEDIA). The average number of Enterococcus faecalis per 1 g of stool was 4.48.108 CFU at the beginning of the study (median 5.25.107 CFU, SD 1.18.109 CFU), while after 14 days of regular daily consumption of the kefir beverage the value determined was 3.32.107 CFU (median 2.65.106 CFU, SD 8.56.107 CFU). The sign test, resultant value u = 4.808326 (critical value 2.58 for statistical significance p = 0.01) showed that the difference in the counts of Enterococcus faecalis in the stool of individuals intervened prior and subsequent to the consumption of kefir beverage was statistically significant, p < 0.01. The counts of Enterococcus faecalis in the stool of individuals after kefir beverage consumption were significantly lower. A subjective evaluation of the women in the questionnaire showed that 93.5 % noticed, after a regular 14 days’ consumption of 200 ml kefir beverage, improved alimentary function in comparison with the period before the study (p< 0.001).