As the porous structure and conductivity result in improvement of electrochemical properties, the chitin nanofibers (ChNFs), multi-walled carbon nanotubes (MWCNTs) and MnO2 (manganese dioxide) nanoflakes 3D porous network core-shell structure gel-film was fabricated for flexible free-standing supercapacitor electrodes. The electrodes were characterized by various techniques and the results demonstrate that the as-synthesized ChNFs/MWCNTs/MnO2 gel-film electrodes exhibits excellent super capacitive behaviours. The ChNFs/MWCNTs/MnO2 gel-film electrode shows a high capacitance of 295.2 mF/cm(2) at 0.1 mA/cm(2) in 1 M Na2SO4 aqueous electrolyte because of its 3D porous structure. Furthermore, the electrodes also showed surprising cycling stability for 5000 cycles with retention rate up to 157.14% at 1 mA/cm(2). The data presents great promise in the application of high-performance flexible supercapacitors with the low cost, light-weight and excellent cycling ability. (C) 2016 Elsevier B.V. All rights reserved.