Carbon　nanotube　(CNT)　suspensions　were　prepared　by　ultrasonic　dispersing　acid-treated　CNT　powders　in　isopropyl　alcohol　solution　containing　magnesium　nitrate　as　ion　carrier.　CNT　films　were　fabricated　on　CrCuCr　electrodes　by　electrophoretic　deposition　using　suspensions　with　different　CNT　concentrations.　The　suspensions　were　characterized　by　UV-vis　spertroscopy.　Results　show　that　when　the　CNT　suspension　concentration　ranged　from　0　to　0.13　g/L,　the　UV-vis　spectra　showed　the　absorption　located　at　258　nm　and　the　absorbance　changed　linearly　with　the　CNT　concentration.　CNT　cathode　prepared　by　electrophoretic　deposition　with　the　CNT　concentration　of　0.12　g/L　presented　good　field　emission　properties,　with　the　turn-on　field　of　0.903　V/μm　and　a　field　emission　current　density　as　high　as　2.903　mA/cm2　at　the　applied　field　of　1.395　V/μm.　UV-vis　spectroscopy　proves　a　viable　method　to　quantitatively　monitor　the　concentration　of　CNT　in　suspension　for　the　purpose　of　depositing　high　quality　CNT　films.