It is acknowledged that an electric double layer capacitor is markedly superior in power density and cycle characteristics to a secondary battery. However, a higher energy density is required to apply it to a power supply of hybrid vehicle, electric vehicle or the like. The present inventors have found that a carbonaceous material containing copper or a compound of copper exhibits excellent characteristics as an electrode material for capacitor and can realize a capacitor having a large capacity. In the electrode material and the capacitor, copper or a compound of copper exists in the amount of 0.8 to 30 parts by weight calculated on the metal basis based on 100 parts by weight of the carbonaceous material, particularly preferably.