Organic dyes effluents are a foremost source of environmental pollution and hence its removal has become an important area of research these days. A series of different concentrations of Lanthanum- Molybdenum Oxide catalysts, LMO (1%, 5%, 10%, 15% and 20wt.%) were prepared by a sol gel method and calcined at 500°C. Thus, synthesized LMO catalysts were characterized by Powder X-ray diffraction analysis (XRD), Flame Emission scanning electron microscopy (FESEM,) Energy-dispersed X-ray analysis (EDX), RAMAN Spectroscopy and Thermo-gravimetric analysis (TGA). The photocatalytic properties of LMO nanoparticles were investigated via methyl orange (MO) and bromothymol blue (BTB) as a model organic compound in aqueous solution under visible light irradiation. More than 80% and 60% degradation of MO and BTB dye within 150 minutes indicating the excellent photocatalytic activity of as prepared catalysts.