An organic light emitting display device may include a substrate including a display area and a non-display area; a thin film transistor on the substrate in the display area; a planarization layer covering the thin film transistor; a first electrode on the planarization layer in the display area and connected to the thin film transistor; a pixel defining layer covering the first electrode and including a first opening that exposes a portion of the first electrode to define an emission area; a first light blocking layer on the pixel defining layer and including a photochromic material, a color of the first light blocking layer being reversibly changed by ultraviolet light; an organic light emitting layer on the first electrode; and a second electrode on the organic light emitting layer.