A display device and a display method are provided. The display device includes a plurality of transparent display units configured to emit imaging light along a same direction and arranged in sequence with spaces therebetween along a light-emitting direction of the imaging light; and a layer-by-layer scan circuit configured to respectively input a plurality of depth images of a same three-dimensional (3D) image into corresponding transparent display units in the plurality of transparent display units, wherein, the plurality of depth images have different depth ranges; and upon each transparent display unit displaying the inputted depth image, the layer-by-layer scan circuit is configured to control transparent display units on a display side of the each transparent display unit to be in a transparent state.