Graphitic　carbon　nitride　hybridized　with　a　small　number　of　carbon　nanotubes　(CNT)　was　synthesized　using　urea　as　precursor.　The　resulting　CNT/g-C3N4　composite　photocatalysts　were　characterized　by　scanning　electron　microscope　(SEM),　transmission　electron　microscope　(TEM),　Fourier　infrared　spectrometer　(FT-IR),　X-ray　diffraction　(XRD),　X-ray　photoelectron　spectroscopy　(XPS),　ultraviolet-visible-near　infrared　Reflection　Spectrophotometer　(UV-Vis-NIR　Spectrophotometer)　and　photoluminescence　spectroscopy　(PL).　Results　indicate　that　the　synergistic　interaction　between　CNT　and　g-C3N4　changed　the　optical　properties　of　bulk　g-C3N4,　affected　the　energy　band　structure,　enhanced　the　absorption　of　visible　light,　optimized　the　distribution　of　the　photogenerated　carrier　and　improved　the　electron-hole　separation　rate.　The　photocatalytic　degradation　of　rhodamine　B　solution　(RhB)　was　performed　under　visible　light　irradiation.　The　photocatalytic　activity　of　CNT/gC(3)N(4)　composite　was　the　highest　when　0.1%(w/w)　CNT　was　loaded　on　the　substrate,　the　rate　constant　for　the　photocatalyst　was　3.1　times　as　high　as　that　of　pure　g-C3N4.　It　was　also　found　that　the　superoxide　radical　was　the　main　active　species　for　catalytic　degradation　in　this　system.