An organic electrolyte capacitor. The organic capacitor is made up of a positive electrode, a negative electrode, and an electrolyte capable of transporting lithium ions. The organic capacitor exhibits a small change in internal resistance during charge and discharge, a high energy and a high output power, and allows lithium ions to move with ease. This is achieved by having a positive electrode that is able to support lithium ions and anions reversibly, a negative electrode that is able to support lithium ions reversibly, and controlling the ratio of positive electrode active material to negative electrode active material within an optimized range.