Graphene　oxide　(GO)　coated　CuO　nanoswire　arrays　have　been　prepared　on　Cu　substrate　as　field　emission　cathodes.　CuO　were　grown　on　Cu　substrates　by　a　low-temperature　hydrothermal　process　and　the　covering　of　GO　sheets　was　carried　out　using　an　electrostatic　self-assembly　method.　The　field　emission　(FE)　investigation　of　GO/CuO　cathode　showed　a　low　turn-on　field　(4.5　V/mu　m)　and　high　enhancement　factor　(1190)　compared　to　those　of　pure　CuO.　The　GO/CuO　composite　nanostructures　are　promising　field　emission　cathodes　in　FE　application.