The influence of an electric field on the color, structure, permittivity, and polymerization of the composite "pre-polymer NOA65-TiO2 nanoparticles" is considered. The electrochromic effect which consists in the restructuring and coloring of NOA65 prepolymer-TiO2 mixture under the action of DC voltage is revealed. The redistribution of TiO2 nanoparticles results in the formation of an opaque structure near the cathode. At the same time, the AC voltage does not essentially influence the composite's structure. The structural and electrical properties of the composites polymerized under different irradiation conditions under the action of a DC voltage are investigated. The mechanisms of restructuring and coloring are discussed.