A transparent display device including a base substrate and a plurality of pixels disposed on the base substrate, each pixel having an emission area and a transmission area transparent to external light, each of the pixels including a circuit element layer disposed on the base substrate, a first electrode disposed on the circuit element layer and corresponding to the emission area, a pixel define layer disposed on the circuit element layer, the pixel define layer including a first sidewall defining the emission area and a second sidewall defining the transmission area, an emission layer disposed on the first electrode and corresponding to the emission area, and a second electrode disposed on the emission layer and including an opening that corresponds to the transmission area, in which the first sidewall is inclined at a first angle, and the second sidewall is inclined at a second angle greater than the first angle.