An organic light emitting diode array substrate, a manufacturing method thereof, and a display device are provided. The organic light emitting diode array substrate includes a base substrate; a first electrode pattern and an insulating layer disposed on the base substrate, wherein the first electrode pattern includes a plurality of first electrodes of strip shape, the first electrodes protrude above the insulating layer to form a step therebetween; an anti-oxidant conductive film disposed on the first electrode pattern and the insulating layer, wherein the anti-oxidant conductive film is disconnected at the step between the first electrodes and the insulating layer.