The catalytic activities of strontium substituted La0.7Sr0.3MnO3 type perovskite catalysts for NO reduction using H-2 as reducing agent has been studied, which is further improved by incorporation of Pt outside (0.1 wt.%Pt/La0.7Sr0.3MnO3) and inside (La0.7Sr0.3Mn0.97Pt0.03O3) the perovskite lattice structure. Pt shows excellent enhancement in catalytic selectivity towards N-2 when supported on the perovskite. The catalysts were characterized using thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and specific surface area. Catalysts evaluations were carried out using thermo-gravimetric analysis coupled with mass spectra (TG-MS).