A power storage device includes a plurality of power storage elements (10) lined up along a predetermined arrangement direction; a dividing member (40) that is made of insulating material and arranged between two adjacent power storage elements; a pair of end plates (31) that sandwich the plurality of power storage elements, and apply restraining force thereto, in the arrangement direction; and a metal connecting member (32) that extends in the arrangement direction and is fixed to the pair of end plates. The dividing member includes a retaining portion (42) that is positioned between the power storage elements and the connecting member, and that retains the connecting member.