In an embodiment, an organic light emitting display device includes a first substrate, a display region, a pad portion, lines, and a moisture-transmission delay layer. The display region includes sub-pixels disposed on the first substrate. The pad portion is disposed on the first substrate and electrically connected to an external device. The lines are disposed between the pad portion and the display region and electrically connected to the external device, and transfer a signal or power to the external device. The moisture-transmission delay layer covers edges of the lines.