A transparent display device includes a color filter substrate, a driving substrate and a polymer-dispersed liquid crystal (PDLC) layer. The color filter substrate includes a substrate, a light shielding structure and a plurality of color filter patterns. The light shielding structure is disposed on the substrate to define a plurality of sub-pixel regions and a blank sub-pixel region of the substrate. The color filter patterns respectively cover the sub-pixel regions of the substrate, but the blank sub-pixel region is not covered by the color filter patterns. The driving substrate corresponds to the color filter substrate. The PDLC layer is interposed between the color filter substrate and the driving substrate.