Using N2 as a doped source to prepare ZnO films, the N-doped ZnO films with strong (002) preferred orientation were deposited on quartz glass substrate by RF magnetron sputtering through changing the ration of O2∶N2. The result shows that the films have a main peak at 402 nm; they have other peaks at 445 nm, 524 nm with the different contents of N, and the intensity of the films are different too; the peak position also produced corresponding red shift or blue shift. When O2∶N2 is 10∶15, the N doping amount of the film is the largest, and the optical performance is the best. The proposed research provides an important reference for the type of ZnO film defect and conductive.