An organic electroluminescent device comprises two substrates facing to each other. The first substrate has a first conductive layer and a pixel array. A second substrate is located on the pixel array, and has a second conductive layer on its lower surface. The pixel array includes a plurality of organic light emitting diodes connected to the first conductive layer. The second conductive layer is electrically connected to the conductive layer, and then electrically connected to a voltage source by way of the first conductive layer.