The present invention relates to an electrochemical capacitor, and provides an electrochemical capacitor which has a fully lowered internal resistance and can yield excellent charging/discharging characteristics. The electrochemical capacitor of the present invention is mainly constituted by an anode and a cathode which oppose each other, an insulating separator disposed between the anode and cathode adjacent thereto, an electrolytic solution, and a casing accommodating them in a closed state. The anode contains a substantially spherical carbon material having an electronic conductivity as a constituent material, whereas the cathode contains a fibrous carbon material having an electronic conductivity as a constituent material.