TiO2-xNx (0.01≦x≦0.2) nanotubes and a method for preparing the same are disclosed. More particularly, TiO2-xNx (0.01≦x≦0.2) nanotubes doped with nitrogen atoms by treating TiO2 nanotubes through nitrogen plasma to partially substitute oxygen portion of TiO2 nanotube with nitrogen, and a method for preparing the same are disclosed. The TiO2-xNx (0.01≦x≦0.2) nanotube of the present invention is prepared by doping nitrogen on a TiO2 nanotube to control an electronic structure and reduce a band gap of the TiO2 nanotube, so that the prepared TiO2-xNx (0.01≦x≦0.2) nanotube exhibits improved conductivity and extended light absorption range from a UV ray area up to a visible light area, thus having more enhanced applicable performance in optical and/or electrochemical aspects.