Zinc acetate/polyacrylonitrile nanofibers were prepared by an electrospinning method. The as-prepared nanofibers were carbonized under argon and washed with acid to obtain porous carbon nanofibers. The surface morphology and microstructure of the porous carbon nanofibers were examined by scanning electron microscopy and X-ray diffraction. The surface area was found to be 413 m(2).g(-1) by the Brunauer-Emmett-Teller (BET) method. The electrochemical performance of the electrodes was characterized by cyclic voltammetry and by chronopotentiogram tests. The results showed that the specific capacitance of the as-repapered carbon porous nanofiber electrode was 275 F.g(-1) under 1 A.g(-1), which is 162% higher than that of the carbon nanofibers without a porous structure.