Wool fibers and products made from them accompany a man almost from the dawn of history. Wool is still the most popular natural material and it is irreplaceable for ecological reasons. However, environmental pollution makes irreversible changes in the structure of wool fibers. Consequently, natural resources of quality precious materials decrease. This situation induces actions which lead to the regeneration of wool fibers. In laboratory conditions wool fiber keratin was exposed to the hydrolytic degradation process in alkaline environment and then the attempt of interruption of this process in the presence of siliceous compounds was made. The changes in the structure of wool fiber keratin were studied by means of Fourier-transform Infrared and Raman Spectroscopy.