The present invention relates to an organic electroluminescence display device capable of reducing the width of wiring without a voltage drop by contacting the lower lines and the upper lines with a contact member such as a solder ball, conductive paste or ACF in a sealing process, thereby forming a double structure of common power supply bus lines and/or cathode bus lines after, when forming source/drain electrodes of thin film transistors, forming lower lines of common power supply bus lines and/or cathode bus lines formed on a peripheral part of the organic electroluminescence display device and forming upper lines at positions on an encapsulating substrate corresponding to the lower lines, and a method for fabricating the organic electroluminescence display device.