Top-illuminating OLED (organic light emitting diode) device and preparation method thereof

The invention provides a top-illuminating OLED (organic light emitting diode) device and a preparation method thereof. The OLED device comprises an electrode substrate, and an oxide layer and a functional layer which are arranged on the electrode substrate; a luminescent layer is arranged on the functional layer; the functional layer is arranged on the luminescent layer; and electrodes are arranged on the functional layer and the oxide layer. The functional layer comprises two combinations, of which one is a hole injection layer and a hole transmission layer, and the other one is an electronic injection layer and an electronic transmission layer. The substrate adopted by the top-illuminating OLED device provided by the invention can be used as the substrate and the electrode, so the OLED device can be directly prepared on the electrode substrate; the preparation cost is saved; and the radiation performance of the device is improved.