To explore structural and thermal stability of Cu/MoO3/SiO2, these mixed oxide systems were subjected to thermal treatments from 5000C to 7000C and were examined by FT-IR, TGA and X-ray diffraction techniques. Cupper based molybdenum supported silica oxide catalyst was prepared by using tetraethyl orthosilicate with different loading of copper on MoO3/SiO2 catalyst such as 1-20wt% by sol-gel method. These catalysts were showed higher stability with nanocrystalline nature. We havealso studied the catalytic activity of theprepared catalyst with oxidation of toluene with green oxidant hydrogen peroxide.