An organic light emitting display device includes a display panel and an optical module. The display panel includes a substrate, a light emitting structure, and a first wall structure. The substrate has an opening region, a peripheral region surrounding the opening region, and a display region surrounding the peripheral region, where a first groove defined in the peripheral region and an opening is defined in the opening region. The light emitting structure is disposed in the display region on the substrate. The first wall structure is disposed within the first groove of the substrate. The optical module is disposed in the opening.