Ordered Ni/Al2O3 core-shell nanowire arrays were prepared in porous alumina membrane via alternating current electrodeposition and chemical etching methods. The shape of the inner Ni core is columnar with a diameter of 50 nm. The shape of the outer Al2O3 shell is a regular hexagon and the well thickness is about 40 nm. This novel structured material can be used as a media for magnetic storage and high-temperature nanoelectronic devices.