The composite of waterborne poly(urethane-acrylate) (WPUA) and antimony doped tin (ATO) was a promising thermal insulation coatings for energy-saving glass. This work demonstrated a sol-gel approach for fabricating WPUA/ATO composites with improved dispersion of ATO nanoparticles. This approach was mainly concerned with the polymerization of CC bonds pre-attached to WPU and ATO nanoparticles. Surface modification was key for achieving a good dispersion of ATO nanoparticles. With UV-assisted initiation, the conversion of CC bonds reached ∼93% in 40s. The comparison study demonstrated that resulting ATO-filled WPUA coatings outperformed those made by physical blending method over the mechanical and optical properties owing to a good dispersion of ATO nanoparticles. In particular, the coatings filled with 3wt% ATO reduced the temperature of a designed “room” by ∼10°C than un-filled counterparts, but merely blocked ∼16% visible light.