The authors have investigated the influence of growth temperature and scandium concentration on the piezoelectric response of scandium aluminum nitride (ScxAl1-xN) films prepared by dual reactive cosputtering. The piezoelectric response strongly depends on the growth temperature and scandium concentration. The piezoelectric response of the films prepared at 400 °C gradually increases with increasing scandium concentration. On the other hand, the piezoelectric response of the films prepared at 580 °C drastically decreases and increases in the scandium concentration from 30% to 40%. We think that the drastic change of the piezoelectric response is due to the disordered grain growth.