A supercapacitor including at least one first electrode substrate having a surface coated with an active material, and at least one second electrode substrate having a surface coated with the active material, wherein the at least one first electrode substrate has a polarity reverse to that of the at least one second electrode substrate. The at least one first and second electrode substrates are stacked in an alternating arrangement. A plurality of the first electrode substrate having the same polarity or a plurality of the second electrode substrate having the same polarity is connected in parallel. The at least one first and second electrode substrates include stacking portions each having opposite surfaces arranged with a frame-shaped insulating ring. An electrolyte is accommodated in spaces enclosed by the opposite surfaces of each stacking portion of the at least one first and second electrode substrates and each insulating ring.