A transparent organic light emitting display device having a pixel region on which an image is displayed and a transparent region through which external light passes. The transparent organic light emitting display device includes a first substrate, a second substrate opposing the first substrate, a display unit disposed between the first substrate and the second substrate, the display unit including an organic light emitting diode. A sealing unit is disposed between the first substrate and the second substrate to surround the display unit and to bond the first substrate to the second substrate. A filling unit is disposed in an inner side of the sealing unit to cover the display unit, the filling unit including a silicon filling material and a photochromic material.