A power storage device according to an aspect of the present disclosure includes: a casing including a bottom wall and a top wall opposite to the bottom wall; a storage battery; an electrical unit; and a cooling unit. The storage battery is disposed in the casing and separated from the bottom wall. The electrical unit is disposed in the casing and located closer to the top wall than the storage battery is. A first fan is disposed between the storage battery and the electrical unit and configured to direct air from the storage battery toward the electrical unit.