A lower electrode 3 including a low-temperature melting layer 3A and a high-temperature melting layer 3B having mutually different melting-start temperatures is provided between a vibration plate 2 and a piezoelectric layer 4. In a calcination step of calcinating the lower electrode 3, the calcination is performed at a low temperature at which only the low-temperature melting layer 3A melts, and in an annealing-process step of the piezoelectric layer 4, the annealing process is performed at a high temperature at which the high-temperature melting layer 3B melts. At this time, in the calcination step, the melting of platinum nano-particles occurs in the low-temperature melting layer 3A, rendering the adhesion and diffusion-preventive effect. Further, in the annealing step, in the high-temperature melting layer 3B, platinum particles are melted, rendering the adhesion and diffusion-preventive effect. The degradation of piezoelectric characteristics of the piezoelectric actuator can be suppressed by the annealing process.