The development of polymeric nanocomposites has invoked much interest in recent years. These nanofillers have great effect on the mechanical, barrier, electrical and thermal properties of base polymers. The present study aims to develop Polypropylene (PP) matrix composite with silica sand nanoparticles. The silica sand nanoparticles with average particle size of less than 100nm was produced by several stages of ball mill and heating combinations. PP matrix composites with 5, 10, 15 and 20 wt. of silica sand nanoparticles were developed through internal mixing and then using injection moulding machine. Physical properties, mechanical behaviour, thermal behaviour and microstructure were studied. It was observed that physical properties increased with increasing content of silica sand nanoparticles in PP. Tensile strength decreased with increasing trend of silica sand nanoparticles however an improvement in flexural strength was observed. DSC analysis shows a reduction in degree of crystallinity of the composites with increasing trend of silica sand nanoparticles. © 2011 IEEE.