Variable resistance nonvolatile memory device and a manufacturing method thereof

A manufacturing method includes forming, on a substrate, lower layer copper lines each being shaped into a strip, forming electrode seed layers each being shaped into a strip, on the respective lower layer copper lines using electroless plating, forming an interlayer insulating layer above the electrode seed layers, forming, in the interlayer insulating layer, memory cell holes, penetrating through the interlayer insulating layer and extending to the electrode seed layers, forming noble metal electrode layers on the electrode seed layers exposed in the respective memory cell holes using the electroless plating, forming, in the respective memory cell holes, variable resistance layers connected to the noble electrode layers, and forming, above the interlayer insulating layer and the variable resistance layers, upper layer copper lines each being shaped into a strip, connected to a corresponding one of the variable resistance layers, and crossing the lower layer copper lines.