An organic electroluminescence (EL) display device assembly includes a substrate, an organic EL portion, an optical loss prevention layer, and a fine space layer. The organic EL portion has a first electrode layer, an organic luminescent layer, and a second electrode layer which are each patterned and stacked on the upper surface of the substrate. The optical loss prevention layer is used to increase light bleeding efficiency. The fine space layer is formed between the optical loss prevention layer and a layer facing the optical loss prevention layer and is filled with a gas or evacuated.