The surface of TiO2 nanoparticles (NPs) was modified by a coupling agent of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane to render them highly compatible with organic monomer mixtures avoiding aggregation. Such TiO2 NPs were then chemically attached with a prepolymer. The refractive index of hybrid TiO2 NPs-polymer was increased dramatically in comparison with that of pure polymer, and it can be controlled by adjusting the content of TiO2 NPs. The Rayleigh scattering of hybrid TiO2 NPs-polymer was size-dependent and increased with the increase of the TiO2 NPs content. When Rayleigh scattering of the hybrid material prepared with a milling and centrifuge process was significantly lowered, one can obtain a transparent sample, which is good for optical devices.