This paper describes 2.2 GHz surface-acoustic-wave (SAW) filters fabricated on ZnO/Al2O3 structures. The single-crystal ZnO films on AL2O3 (sapphire) substrates have been grown by rf magnetron sputtering and are found to exhibit excellent SAW properties. Minimum line-width of electrodes used for the filter is 0.875 µm. High phase velocity of a higher order mode in the substrate structure and harmonic generation by split electrodes make it possible to use such wide electrodes even at 2.2 GHz. The filter has shown considerably low insertion loss of 12.5 dB at the center frequency.