The aim of this study was evaluation of relationship between the ability of extracellular slime production and adhesive properties of E. coli strains. This study included 169 of E. coli strains isolated from urine and blood samples. All of these strains were isolated in the Clinical Microbiology Department of dr. A. Jurasz University Hospital in 2003-2006. After incubation in BHI and TSB medium adherence to polystyrene demonstrated 28 (16.6%) and 20 (11.8%) of E. coli strains, respectively. Strains incubated in TSB medium demonstrated higher production of extracellular slime than strains incubated in BHI medium. Non-adhering strains were producing more extracellular slime than adhering strains both after incubation in BHI as well as TSB medium.