The pure SrTiO3 nanoparticles were synthesized  by sol-gel method and Ag2O loaded SrTiO3 (Ag2O/SrTiO3) was prepared by precipitation method. The obtained samples were characterized with powder X-ray diffraction (XRD), transmission electron microscope (TEM) and UV-visible diffuse reflection spectrum (DRS). The effect of Ag2O loading on the photocatalytic activity of Ag2O/SrTiO3 nanoparticles for the degradation of methyl orange (MO) as amodel pollutant under visible light irradiation was studied. Compared with pure SrTiO3 nanoparticles, the Ag2O/SrTiO3 nanoparticle displayed higher photocatalytic activity for the degradation of methyl orange and the 5 % Ag2O/SrTiO3 photocatalyst exhibited the highest photocatalytic activity.