Ni-doped Cu3N films were prepared by radio frequency (RF) reactive magnetron sputtering method under different N2/(N2+Ar) ratios at room temperature. X-ray diffraction (XRD) patterns show that Ni-doped Cu3N films have the preferred growth along the (100) plane. The lattice parameters of Ni-doped Cu3N films increases obviously compared with the pure Cu3N films, which indicate that some Ni atoms are incorporated into the Cu3N host lattice. The electrical resistivity of Ni-doped Cu3N films has a remarkable change and decreases as the nitrogen ratio decreases. The optical energy gap of Ni-doped Cu3N film is around 1 eV which has no obvious change. The morphology and the thermal stability of doped Cu3N films were also studied.