A method for manufacturing a piezoelectric actuator (21 a) as a piezoelectric element includes: an electrode forming step of forming a lower electrode (24) on a base body (27) including at least a support substrate (22); a film forming step of forming a piezoelectric thin film (25) on the lower electrode (24); a patterning step of patterning the piezoelectric thin film (25) by removing a part of the piezoelectric thin film (25); and a polishing step of polishing the support substrate (22). The polishing step is performed before the patterning step. In the film forming step, the piezoelectric thin film (25) is formed such that a ratio of the peak intensity of a pyrochlore phase to the sum of the peak intensities of (100) orientation, (110) orientation, and (111) orientation of a perovskite phase, obtained by 2θ/θ measurement of X-ray diffraction, is 100 ppm or less.