An image grouping device which may comprise a first classifying unit for classifying a plurality of items of image data in a first predetermined unit, a second classifying unit for breaking the plurality of the items of image data classified by the first classifying unit into smaller groups in a second predetermined unit, and a control unit for controlling the plurality of the items of image data classified by the second classifying unit to be displayed on a display. The control unit may automatically select a background image according to background music during a slide show.