Interest in flexible, safe and light weight energy storage devices based on nanocomposites meet the various requirements of modern technology. The performance characteristics of energy devices are fundamentally determined by struct ural and electrochemical properties of electrode material. Electrolyte choice (aqueous or non-aqueous), li miting power capability and packaging designs is the other important factor in supercapacitor and batteries. In presen t study, multiwall carbon nanotube (MWNT)/polystyrene (PS) nanocomposites have been synthesized by solution cast method and characterized by X-ray diffraction (XRD), dynamical mechan ical analysis (DMA), dielectric analysis and cyclic voltammetric measurements for their use in energy storage system. Enhancement in ca pacitance due to incorporation of MWNTs in polymer matrix reveals availability of mo re specific surface area as well as conductivity.