ZnO thin films were prepared on glass and (012) sapphire substrates by rf magnetron sputtering. Polycrystalline ZnO films with a (002) orientation were obtained on glass substrates. (110) ZnO films were epitaxially grown on the (012) sapphire substrates. Surface acoustic wave properties were also measured for propagating along the c axis of ZnO film on the glass and sapphire substrates. The phase velocities (V_P) on glass and sapphire substrate at center frequency were 2&80 m/sec and 5980 m/sec and the effective coupling coefficient (k²) on the 0th mode were 0.98 % and 1.43 % respectively.