Provided are an electrode for a power storage device having much better charge/discharge characteristics and a power storage device using the electrode. A plurality of cavities is provided in a surface of an active material layer over a current collector. A graphene covering the active material layer facilitates rapid charge/discharge and prevents breakdown of the current collector caused by charge/discharge. With improved charge/discharge characteristics, an electrode for a power storage device which does not easily deteriorate and a power storage device using the electrode can be provided.