The main purpose of this study was to evaluate the structural transformation in rats' tongue tissue after oral administration oflead salts. Under the conditions of acute experiment during 5 days Wistar rats were orally administered the lead acetate solution in the amount of 24 mg per day. Histological studies were carried out at OSMU upon the completion of the experiment. Effect of toxic doses oflead results in symptoms of both hyperkeratosis and destruction of tongue tissue. It is assumed that the oxidative stress and tissue irritation, induced by lead intoxication, causes pathological changes in the shape, height and number of filiform papillae of the tongue. This results in hyperkeratosis, hydropic degradation of the epithelium and in the presence of an inflammatory infiltrate in the connective tissue.