This study focuses on the preparation and properties of CeO2-SiO2 thin films with thickness ≤60 nm that can be used as protective coatings for solar cell panels and electrochromic counter electrodes. Thin-film CeO2-SiO2 systems on glass and quartz substrates, which are manufactured from film-forming solutions based on cerium(III) nitrate, salicylic acid, and tetraethoxysilane and thermally treated, are mixtures of cerium(IV) (cubic modification) and silicon(IV) (amorphous phase) oxides. The films synthesized are distinguished by a net structure and high visible transmittance (∼90-100%). The morphology, phase composition, and optical properties of films were studied by X-ray diffraction, X-ray spectral microanalysis, scanning electron microscopy, spectrophotometry, and ellipsometry.