This paper represents the results of the study, carried out by the methods of molecular optics, of nanostructures formed in a process of reduction of ionic selenium in selenite-ascorbate redox system in aqueous solutions of high molecular polymeric stabilizers of anion type. We conclude that due to adsorption of macromolecules of strong acids on the nanoparticles of selenium the spherical nanoparticles of similar morphological types with similar dimensions, densities and widths of a polymer shell are formed.