An organic light emitting display device includes a substrate, a first transistor disposed on the substrate in the opaque region, a second transistor disposed on the substrate in the opaque region, the second transistor being adjacent to the first transistor along a first direction, and a capacitor disposed on the substrate in the opaque region, the capacitor being adjacent to the first transistor along a second direction different from the first direction. Here, the capacitor may include a first capacitor electrode, a dielectric structure including silicon oxynitride and a second capacitor electrode.