Carbon nitride films have been deposited by vacuum cathodic are method at various arc currents while keeping the flow of Ar/N-2 at a constant value. The films were characterized by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. During the deposition, the total pressure kept the falling tendency upon the increasing of the arc currents. The N content of the films varied over the range of 15-32 at.%. The films mainly consisted of three types of bonds: CC bonds, sp(2) CN bonds and sp(3) CN bonds besides CO and NO bonds. The sp(2) CN bonds dominated in the films relative to sp(3) CN bonds. Raman spectra and XPS indicated that the films showed different properties according to the arc currents. At 20 and 30 A, the films demonstrated the high N concentration and the characteristic of polymer-like material. With the increase of arc currents, the films became more and more disordered due to the energy enhancement of species in the atmosphere and transformed from the polymer-like microstructure to the type similar to amorphous carbon at 40 A and the sp(3) CN ratio also kept the rising tendency. Above 40 A, some new Raman peaks were observed, which suggested some new microstructure appear and be embedded in the amorphous matrix. Meanwhile the N content dropped relative to that at low arc currents and both the sp CN ratio and the N content kept a little higher value at 60 A than those at 50 and 70 A due to the dominance of the new microstructure.