According to one embodiment, a storage device includes an enclosure, and a circuit board assembly in the enclosure. The circuit board assembly includes a first circuit board, a second circuit board opposed to the first circuit board, a third circuit board opposed to the second circuit board, a first connector connecting the first and second circuit boards to each other, a second connector connecting the second and third circuit boards to each other, and is offset to the first connector in a plane direction, a first spacer between the first and second circuit boards, and a second spacer between the second and third circuit boards. The first spacer includes a support body at a position opposed to the second connector and in contact with the first and second circuit boards.