The article deals with the results of biochemical and biophysical search of hoof horn of clinically healthy cows and patients with purulent pododermatitis. It is known that the development of the inflammatory process in the area of the hoof, in particular, for purulent inflammation of the producing layer of the skin, affects not only the general condition of the organism of animals, but also the biochemical indices of the hoof horn of the cows. Thus, in the epidermis of cows hoof for purulent pododermatitis, there is a probable increase by 3.7% moisture content and by 26.8% – the concentration of SH-groups in the tendency to reduce the concentration of ash, fat and protein. These changes indicate a slowdown in the keratinization and accumulation process, as a result, in the hoof horn of the epidermis, excessive moisture content. It was found that other biochemical indices influence the state of the hoof horn, in particular, the concentration in the epidermis of the hemispheres of sulfur, keratoses, calcium. Thus, for purulent pododermatitis, the sulfur content decreases by 17.1%, calcium – 12.3%, which indicates a deterioration of keratinization processes, which is confirmed by the redistribution of sulfur concentration in keratoses, namely an increase of 2.9% of the contents of a-keratosis and 3.7% was g-keratosis. In the process of keratinization, microelements, in particular copper and zinc, play an important role. For purulent inflammation of the producing layer of the skin of the cows hoof, a decrease in the concentration of these mineral substances is observed on 17.9 and 13.9%, respectively. Changes in the biochemical indices of the epidermis in the cows hoof for purulent pododermatitis also affected its biophysical properties. Thus, the density of the hoof horn was decreased by 7.3%, and the hardness by – 2.5%. Consequently, purulent pododermatitis is accompanied by changes in certain biochemical and biophysical parameters of the hoof horn, which reflects the processes occurring in the epidermis of hoof and is one of the triggers of the development of inflammation of the skin of the cows hoof.