Novel organic –inorganic nanocomposite hybrid materials have been prepared by a sol-gel process. Tetraethoxysilane (TEOS) was used as inorganic source. Polyurethane acrylate (PUA) was the organic segment. 3-(trimethoxysilyl)propyl methacrylate (KH-570) was used as both a secondary inorganic source and a silane coupling agent to improve the compatibility of the organic and inorganic phases. X-ray diffraction indicates that silica was equally dispersed in polymer matrix. Furthermore, silica and polymer formed interpenetrating polymer network. Thermal property of the hybrid materials were checked by TGA study.