N-incorporated ZnO films were fabricated using rf magnetron sputtering under different nitrogen flow rates (P N ). The surface roughness and ZnO grain size are dependent on P N . Meanwhile, Zn nitride appears in the films as P N increases. N incorporation affects the intensity of the diffraction peaks from the different lattice planes. At P N =20%, the film grows with ZnO (002) lattice. The incorporated N exists in the forms of Zn nitride and atomic N. The optical band gap (E g ) of the N-incorporated ZnO films decreases from 3.17 to 2.95eV linearly with the increase of P N . The photoluminescence peaks in the region of 2.4–2.7eV come from the transition between conduction band edge and oxide antisite defects (O Zn ), and also be influenced by oxygen vacancies (V o ).