One-dimensional　CuO　nanostructure　arrays　have　been　synthesized　on　Cu　foil　by　a　low-temperature　wet　chemical　process.　Different　CuO　nanostructures　including　nanorods　with　facet　heads,　nanorods　with　needle-like　tips　and　nanotubes　are　shaped　simply　by　varying　the　concentration　of　oxidant.　Field　emission　measurements　show　that　CuO　nanorods　with　needle-like　tips　are　of　superior　performance　than　other　shapes,　having　a　turn-on　field　of　3.5V/μm　and　a　field　enhancement　fact　or　of　2107.　The　good　field　emission　performance　is　assigned　to　the　sharp　tips　contributing　to　the　high　field　enhancement　effect　and　to　the　moderate　density　reducing　the　field　screening　effect.　©　2014　Chinese　Institute　of　Electronics.