A removable data-storage device. The removable data-storage device includes a main data-storage unit, an exterior housing for containing the main data-storage unit, an elastic shock-reduction part between an inner wall of the exterior housing and the main data-storage unit for reducing a mechanical shock to the main data-storage unit by elasticity and an external connector exposed from an opening of the exterior housing. The main data-storage unit is placed at the rear of the external connector as viewed from the opening. The external connector is joined and secured to the main data-storage unit and the exterior housing. In addition, the elastic shock-reduction part is configured to deform with a movement of the main data-storage unit in the exterior housing produced by a mechanical shock and a movable range of the external connector is smaller than a movable range of the main data-storage unit.