Strontium titanate (SrTiO3) and chromium doped SrTiO3 (Cr/SrTiO3) were prepared by modified sol-gel method with the citric acid as a chelating agent in the ethylene glycol solution for the effective photodegradation of methylene blue dye under visible light irradiation. The synthesized doped and un-doped SrTiO3 nanoparticles were structurally characterized and their photoresponse performances for the efficient degradation of methylene blue dye have been demonstrated. After introducing the Cr on SrTiO3, UV-Vis absorption was appeared the red-shift at 566 nm from 392 nm as compare with bare SrTiO3. The photocatalytic degradation activity of Cr/SrTiO3 was significantly improved to 60% degradation of methylene blue in 3 h under visible light, which is approximately 5 times higher than that of the bare SrTiO3.