An organic EL display device includes a first substrate, a plurality of organic EL devices arranged on the first substrate, a second substrate arranged above the first substrate, and a filling layer arranged between the first substrate and the second substrate, and displays an image on the second-substrate side. The organic EL display device is characterized in that: the organic EL devices each have a light-emission layer, a reflection electrode formed below the light-emission layer and reflecting light from the light-emission layer upwards, and an upper electrode formed above the light-emission layer and having a light transmission property and reflectivity; a structure for resonating the light emitted by the light-emission layer is formed between the reflection electrode and the upper electrode; and the filling layer includes fine particles for diffusing light exiting from the upper electrode added therein.