The epithelial cell surfaces of neonatal Wistar rat tongue mucosa were examined by transmission electron microscopic method. The tissues were fixed by modified Karnovksy solution and embedded in Spurr resin. Thin sections of 90 nm thickness were cut and examined in the Jeol 1010 transmission electron microscopy. It was revealed that the queratinized squamous epithelial cells of the tongue mucosa exposed to cadmium presented groupings of numerous bacteriae which are attached to the flat cell membrane surfaces. The coccus and bacillus are attached to the cell membrane in organized rows or at random, as clearly seen in the TEM images. At high magnification, the transmission electron microscopic images showed that bacteriae are attached by a fibrillar structures from each other and from epithelial cell membrane and bacteriae. The control group analysis demonstrated that the cell membrane didn´t show the presence of bacteriae