Flexible supercapacitor is successfully fabricated using polyaniline nanowires/carbon cloth (PANI-NWs/CC) nanocomposite. High gravimetric capacitance of 1079 F g(-1) at a specific energy of 100.9 Wh kg(-1) and a specific power of 12.1 kW kg(-1) is obtained. Moreover, this approach also offers an exceptionally high area-normalized capacitance of 1.8 F cm(-2). The diffusion length of protons within the PANI-NWs is estimated to be about 60 nm by electrochemical impedance analysis, which indicates that the electrochemical performance of the electrode is not limited by the thickness of PANI-NWs. The electrochemical performance of PANI-NWS/CC remains without any deterioration, even when the cell is bent under high curvature. These results clearly present a cost-effective and simple method of fabrication of the nanostructured polymers with enormous potential in flexible energy storage device applications. (C) 2010 Elsevier B.V. All rights reserved.