A　novel　magnetically　controlled　Ni-plating　method　has　been　developed　to　improve　the　field-emission　properties　of　carbon　nanotubes　(CNTs).　The　effect　of　the　magnetic　field　and　Ni-electroplating　on　CNT　field-emission　properties　was　investigated,　and　the　results　are　demonstrated　using　scanning　electron　microscopy,　J　-　E　and　the　duration　test.　After　treatment,　the　turn-on　electric　field　declines　from　1.55　to　0.91　V/μm　at　an　emission　current　density　of　100　μA/cm2,　and　the　emission　current　density　increases　from　0.011　to　0.34　mA/cm2　at　an　electric　field　of　1.0　V/μm.　Both　the　brightness　and　uniformity　of　the　CNT　emission　performance　are　improved　after　treatment.　©　2011　Chinese　Physical　Society　and　IOP　Publishing　Ltd.