The dispersion curves (phase velocity and electromechanical coupling coefficient) of ZnO(a plane)/sapphire(r plane) structure are obtained by theoretical calculation. A SAW filter with ZnO/sapphire structure is designed based on the calculating results. The SAW filter prototype is fabricated by depositing ZnO film on sapphire substrate and then fabricating chip. In the process, the aplane ZnO thin film has been grown. Three SAW modes of the thick film sample, named mode 0, mode 1 and mode 2, are measured. The measured center frequency of mode 0 and mode 1 and mode 2 is 1 073.79 MHz, 1 290.63 MHz and 1 572.3 MHz respectively. The measured phase velocity of mode 0 and mode 1 and mode 2 is 3 865.67 m/s, 4 646.25 m/s and 5 660.27 m/s respectively.