Abstract: Nano-sized nickel oxide （NiO） was synthesized by using low cost and porous cotton fiber as natural template in conjunction with sol-gel approach for the first time.Firstly,the template-sol system was prepared by immersing sol into cotton fiber.Then it was converted into template-gel system by drying.Finally,prepared complex precursors were thermally decomposed and template was removed simultaneously by annealing at 600 ℃ for 6 h to obtain nano-NiO samples.Crystal formation,size,and morphology of the obtained samples were characterized by X-ray diffraction （XRD） and transmission electron microscopy （TEM）.Their electrochemical performance was preliminarily discussed by cyclic voltammetry and galvanostatic charge/discharge measurements.Results of XRD showed that sample was cubic NiO.TEM test results indicated prepared NiO displayed spherically and its average size was about 60 nm.In addition,electrochemical measurements indicated prepared NiO electrodes had a good stability and cyclic performance,and their specific capacitance as single electrode was up to 360 F/g in 6 mol/L KOH electrolyte with the potential range from 0 to 0.4 V（vs SCE.）