Vertically　aligned　CuO　nanowires　are　coated　with　CNT　network　films　to　achieve　a　significant　improvement　in　field　electron　emission.　The　turn-on　field　of　CuO　nanowire　array　cathodes　is　decreased　from　6.6　V/μm　to　below　1.2　V/μm　owing　to　the　CNT　film　coating.　Compared　to　the　needle-like　CuO　structures　that　could　perforate　the　CNT　film　coating,　CuO　nanowires　with　uniform　diameter　are　more　suitable　to　be　wrapped　by　CNT　network　films　from　top　to　bottom.　It　is　found　that　the　coverage　of　CNTs　over　CuO　nanowire　surface　plays　a　role　in　affecting　the　turn-on　fields　and　emission　stabilities.　©　2015　Elsevier　Ltd.　All　rights　reserved.