Sophisticated preparation of arbitrarily long conducting nano wire electrodes on a large area is a significant requirement for development of transparent nanoelectronics. We report a position-customizable and roomtemperature-processable metallic nanowire (NW) electrode array using aligned NW templates and a demonstration of transparent all-NW-based electronic applications by simple direct-printing. Well-controlled electrolessplating chemistry on a polymer NW template provided a highly conducting Au NW array with a very low resistivity of 7.5 mu Omega cm (only 3.4 times higher than that of bulk Au), high optical transmittance (>90%), and mechanical bending stability. This method enables fabrication of all-NW-based electronic devices on various nonplanar surfaces and flexible plastic substrates. Our approach facilitates realization of advanced future electronics.