A storage device includes a shutter having a vertically divided dome shape formed by cutting a one-end-closed cylindrical shape at two planes, the one-end-closed cylindrical shape being formed by closing an upper end of a cylindrical portion whose axis line is along an up-down direction, an arc-shaped lower portion reinforcing member which has a higher rigidity than the cylindrical portion, a housing, which includes an opening portion, the opening portion being opened and closed by the shutter rotating around the axis line, a bearing portion provided in the housing, which suspends and supports the ceiling surface portion, a lower end support portion, which supports a lower surface of the lower portion reinforcing member at a plurality of locations; and an inner side support portion, which supports an inner peripheral surface of the lower portion reinforcing member at a plurality of locations.