The electro-optical studies of composite particles built from a large anisodiametric particles with much smaller spherical particles are of great interest in at least three directions. According to the distribution of the components in the particles, composite particles can be classified into two different types: internally composite particles and externally composite particles. Various composite materials prepared via heterocoagulation are applied to obtain porous ceramics, pharmaceutical and drug delivery systems, organo-inorganic composites, catalysts or catalyst carriers and adsorbents. The correlation between the polarizability of the composite particles and the electrokinetically mobile charge confirms the assumption that within the kilohertz region the orientation of composites is due to the polarization of a part or of the entire diffuse layer. The application of electro-optics in the study of nanocomposites is of a great interest because the materials produced by heterocoagulation of anisodiametric and spherical particles are of both theoretical and practical interest.