A series of mesoporous TiO2/SBA-15, Cu/TiO2 and Cu/TiO2/SBA-15 composite photocatalysts were prepared by sol-gel synthesis for photoreduction of CO2 with H2O to methanol. It was found that optimum amount of titanium loading of TiO2/SBA-15 was 45 wt% which exhibited higher photoreduction activity than pure TiO2. An addition of copper on TiO2 or TiO2/SBA-15 catalyst as cocatalyst was found to enhance the catalytic activity because copper serves as an electron trapper and prohibits the recombination of hole and electron.