Micro-supercapacitors, as micro-scale energy storage units, are envisaged to provide the necessary power to miniaturized electronics. Here we report, copper oxide nanowire micro-supercapacitors, developed on a printed circuit board (PCB), following a facile pattern transfer and electrochemical forming protocol. In this way, a PCB can be patterned into a largescale interdigital electrode array, on which copper oxide nanowires can be grown electrochemically in a single step. The copper oxide nanowires micro-supercapacitor demonstrated a maximum areal capacitance of 257 mF cm−2 (659 mF cm−2 in aqueous KOH solution), maximum energy density 35 μWh cm−2 and power density 5.2 mW cm−2 in the solid-state PVA-H2SO4 gel electrolyte. The significant performance parameters showed the potential of direct patterning of PCB to nanostructure microelectrodes on a large scale for micro-supercapacitor.