An organic light emitting display device includes a substrate including a plurality of pixel regions each including a light emitting region and a transparent region, a gate electrode in the light emitting region, a first insulating interlayer covering the gate electrode and extending from the light emitting region to the transparent region, a drain electrode on the first insulating interlayer and constituting a transistor in conjunction with the gate electrode, a planarization layer covering the transistor and exposing a top surface of the first insulating interlayer in the transparent region, and a first electrode on the planarization layer.