An electric double-layer capacitor, which provides enhanced heat release-ability with a simple configuration ensuring vibration resistance and impact resistance and to improve durability in a severe marginal environment, is provided. The electric double-layer capacitor includes capacitor cells; a pair of end plates, respectively disposed on both sides of a plurality of parallelly arranged capacitor cells; a metallic case for housing the end plates, a plurality of capacitor cells; and an insulating resin, filling the interior of the metallic case to cover the end plates, a plurality of capacitor cells and lead terminals, wherein the electric double-layer capacitor further includes an external connecting terminal having two end sections, one of the end sections being disposed in the end plate within the insulating resin, and wherein the lead terminal of the capacitor cell disposed adjacent to the end plate is configured to be connected to the one of the end sections of the external connecting terminal.