A novel multifunctional UV-curable waterborne polyurethane acrylate (WPUA) was synthesized from polycaprolactone diols(PCL), isophorone diisocyanate(IPDI), dimethylol propionic acid (DMPA) and pentaerythritol triacrylate(PETA). Waterborne UV-curable hybrid materials were prepared from WPUA as organic phase and γ-trimethoxysilyl-propyl methacrylate (TMSPM) modified nanosilica as inorganic phase. The structure of products was characterized by FT-IR spectrum, and the surface morphology, thermal stability, UV curing kinetics and mechanical properties of hybrid films were investigated. The results showed that the structure was identified and the modified nanosilica was dispersed into hybrids homogeneously and stably. Furthermore, it has been found that the thermal stability and mechanical properties of hybrid films were improved with the addition and increase of nanosilica, while the curing rate and final gel content were still in good levels.