The ability of four strains of Lactobacillus sp. two strains of Bifidobacterium sp. and one strain of Listeria mnocytogenes to adhere to human intestinal cell lines Caco-2, HT-29 and Int 407 was examined. Well-developed monolayers of intestinal cells were obtained when initial concentration of Caco-2 cells was 1 x 104/cm2, HT-29 cells 4.2 x 104/cm2, and Int 407 cells 2 x 104/cm2. The appropriate fetal bovine serum additions for Caco-2, HT-29 and Int 407 were 20%, 10% and 10%, respectively. The reduction of serum addition decreased intestinal cell density and prolonged monolayer development. The highest cell densities in epithelial monolayer were obtained in the Int 407 cell cultures. The yield of bacterial adhesion was strain ? dependent. Significant differences were also observed in bacteria adhesion to individual intestinal cell lines. The best adhesion ability to Caco-2 exhibited Lactobacillus rhamnosus GG and Bifidobacterium bifidum. The highest adhesion to HT-29 line demonstrated B. bifidum and Lactobacillus acidophilus LC1. The adhesion of bacteria to Int 407 was much lower. Significant effect on bacteria adhesion has their cell density being in contact with intestinal monolayer. The adherence of Listeria monocytogenes to Caco-2 and HT-29 was very low in the range of 0.2% and 6.0%, respectively.