The direct photoconversion of carbon dioxide and methane is investigated in an appropriate gas-phase batch reactor under visible light irradiation. WO3 nanoparticles coated on stainless steel webnet have used as photocatalyst. WO3 nanoparticles are synthesized and characterized by SEM, XRD, EDX, FTIR and UV-vis spectra analyses. SEM images indicate that WO3 nanoparticles were well coated on the surface of the webnet. The XRD analysis confirm monoclinic structure and average particle size about 100 nm for the WO3 nanoparticles. Also, the FTIR analysis exhibit the structure of tungsten oxide. The results of UV-vis show that the visible light absorbance spectrum of WO3 are more efficient than TiO2 and ZnO. The conversions of 28% and 13.3% for CO2 and CH4 has been found by WO3 under visible light, respectively.