A secondary battery with a novel structure that can be bent repeatedly is provided. In the secondary battery, an exterior body includes a front surface, a back surface, a first sealing portion, and a second sealing portion. The front surface includes a first long side, a second long side, a third side, and a fourth side. The third side and the fourth side face each other. The third side and the fourth side are substantially perpendicular to the first long side. The front surface includes a third sealing portion. The first sealing portion is along the third side. The second sealing portion is along the fourth side. The third sealing portion includes a region overlapping with the first sealing portion and a region overlapping with the second sealing portion. At least one of the first terminal and the second terminal overlaps with the first sealing portion.