The effect of different synthesis techniques on structural, microstructural and electrical properties of La0.7Sr0.3MnO3 (LSMO) was investigated. Two different techniques viz solid state reaction (SSR) and sol-gel (SG) method were used to prepare the samples. X-ray studies have confirmed the single phase formation of LSMO by both the techniques. The average grain size was 2 m for solid state reaction sample and 22 nm for sol-gel sample. A substantial enhancement in electrical resistivity was observed in the sample with nanosized grains. The micro grain size sample exhibited metallic behaviour whereas nanoparticle sample showed metal-insulator transition around 250 K.