The aluminum nitride(AlN) films with (002) preferential orientation were prepared by IF magnetron sputtering on quartz substrates. The preferential orientation and surface morphology of AlN were characterized by X ray diffraction(XRD) and scanning electron microscope(SEM). The experimental results show that the properties of AlN films are dependent on the sputtering power, nitrogen flow rate and argon plasma cleaning. The bulk acoustic wave microwave delay line was fabricated by using the prepared AlN film. The frequency of 4.2～4.4 GHz, delay time of 361 ns, insertion loss of -57.3～-60.4 dB, triple transmitting suppression(TTS) of 28.6 dB, feed through suppression of 52.7 dB have been achieved.