The present invention discloses a transparent display device comprising a display panel, an array of polarization light splitting sheets provided on the side of the display panel on which no polarizer is provided, and at least one polarization light sources provided at a side of the array and emitting a polarized light polarized along a certain direction towards an inner surface of at least one polarization light splitting sheets in the array. The polarized light polarized in the certain direction, emitted by a corresponding polarization light source and incident onto the inner surface of the polarization light splitting sheet can be reflected to the display panel, and the polarized light polarized in a direction perpendicular to the certain direction, coming from an ambient light and incident onto an outer surface of the polarization light splitting sheet can be transmitted to the display panel.