The bacterium Enterococcus faecium is a commensal organism in the microbiota of the human digestive system, but we also find it in the environment, soil, water, food, plants and animals. These cocci are also considered opportunistic pathogens because they can sample various infections in humans. The aim of this study is to test the sensitivity of the collected bacterial strains of E. faecium to the antimicrobial drug vancomycin and to test the following virulence factors; biofilm formation, β-hemolytic activity and hydrophobicity of the cell surface. 90 strains of Enterococcus faecium bacteria were collected from three different sources; clinical samples from the hospital environment, food and waste water. 30 strains were taken from each source. Testing the sensitivity of the strains to the antibiotic vancomycin showed that the largest number of resistant strains were collected from the hospital environment and testing the ability to form biofilms showed that strains isolated from hospitals and food are significantly better biofilm producers than strains isolated from wastewater. Also, it was determined that isolates from food have the highest hydrophobicity of the cell surface and testing the β-hemolytic activity of 90 strains revealed that only six strains are β-hemolytically active; three isolates from food, two from the hospital and one from waste water. From the examined vancomycin-resistant (VRE) strains, no correlation was observed between the virulence factors of cell surface hydrophobicity and biofilm formation under in vitro conditions. However, the test was conducted on a small sample of VRE strains and a general conclusion of a possible correlation cannot be drawn. From the obtained data, it can be concluded that there is a difference in virulence factors between the isolated strains of E. faecium bacteria, therefore the initial hypothesis proved to be correct.