The invention relates to a preparation method for carbon-coated nickel oxide NiO / C as a supercapacitor electrode material, comprising the steps that (1) nickel acetate Ni (CH3COO)2.4H2O, urea and polyvinylpyrrolidone are dissolved in absolute ethyl alcohol and water and stirred, so that a mixed solution is obtained; (2) the mixed solution is subjected to hydrothermal reaction, and after the reaction is finished, the mixed solution is cooled, centrifuged, rinsed, dried and calcined, so the NiO material is obtained; (3) the NiO is dissolved in a glucose solution and stirred, to obtain a mixed solution, the mixed solution is subjected to hydrothermal reaction, and after the reaction is finished, the mixed solution is cooled, centrifuged, rinsed, dried and calcined, so that the carbon-coated nickel oxide NiO / C is obtained. The NiO / C electrode material prepared by the method disclosed by the invention is in porous structure and has high specific surface area, meanwhile the overall conductivity of the NiO electrode material can be improved due to the carbon layer, and the carbon and the NiO have synergistic effect, so that the specific capacitance and speed ratio capacitance, and the NiO / C is an excellent supercapacitor electrode material.