A shape-retaining hoist type rectangular parallelepiped bag comprising: a rectangular parallelepiped bag that is a generally rectangular parallelepiped-shaped bag that has an internal space to accommodate an accommodated object; a bottom surface holding mechanism configured to hold a bottom surface by application of a tensile force thereto; a side surface holding mechanism configured to hold a side surface by application of a tensile force thereto; a central hanging body configured to extend in a vertical direction with one end thereof being fixed to a center of the bottom surface of the rectangular parallelepiped bag and hold the bottom surface holding mechanism and the side surface holding mechanism at intermediate positions in the vertical direction; and a ring-shaped hook holding portion connected to the other end of the central hanging body, to which a hook is to be attached, characterized in that: the bottom surface holding mechanism includes at least four hanging bodies with one ends thereof being fixed at positions spaced apart from the center of the bottom surface by a predetermined distance on diagonal lines connecting between opposed apexes of the bottom surface, and the other ends thereof being fixed to the central hanging body; the side surface holding mechanism includes a plurality of side surface restriction bodies that have horizontal components of vectors extending in directions different from those of the hanging bodies as viewed downwardly in the vertical direction from a top surface with one ends of the side surface restriction bodies being fixed to the side surfaces; and the other ends of the side surface restriction bodies are connected in between a hanging body connected portion to which the other ends of the hanging bodies and the central hanging body are connected, and the other end of the central hanging body. a rectangular parallelepiped bag that is a generally rectangular parallelepiped-shaped bag that has an internal space to accommodate an accommodated object; a bottom surface holding mechanism configured to hold a bottom surface by application of a tensile force thereto; a side surface holding mechanism configured to hold a side surface by application of a tensile force thereto; a central hanging body configured to extend in a vertical direction with one end thereof being fixed to a center of the bottom surface of the rectangular parallelepiped bag and hold the bottom surface holding mechanism and the side surface holding mechanism at intermediate positions in the vertical direction; and a ring-shaped hook holding portion connected to the other end of the central hanging body, to which a hook is to be attached, characterized in that: the bottom surface holding mechanism includes at least four hanging bodies with one ends thereof being fixed at positions spaced apart from the center of the bottom surface by a predetermined distance on diagonal lines connecting between opposed apexes of the bottom surface, and the other ends thereof being fixed to the central hanging body; the side surface holding mechanism includes a plurality of side surface restriction bodies that have horizontal components of vectors extending in directions different from those of the hanging bodies as viewed downwardly in the vertical direction from a top surface with one ends of the side surface restriction bodies being fixed to the side surfaces; and the other ends of the side surface restriction bodies are connected in between a hanging body connected portion to which the other ends of the hanging bodies and the central hanging body are connected, and the other end of the central hanging body. the bottom surface holding mechanism includes at least four hanging bodies with one ends thereof being fixed at positions spaced apart from the center of the bottom surface by a predetermined distance on diagonal lines connecting between opposed apexes of the bottom surface, and the other ends thereof being fixed to the central hanging body; the side surface holding mechanism includes a plurality of side surface restriction bodies that have horizontal components of vectors extending in directions different from those of the hanging bodies as viewed downwardly in the vertical direction from a top surface with one ends of the side surface restriction bodies being fixed to the side surfaces; and the other ends of the side surface restriction bodies are connected in between a hanging body connected portion to which the other ends of the hanging bodies and the central hanging body are connected, and the other end of the central hanging body.