A method of producing a piezoelectric actuator includes a first electrode film forming process; a monomolecular film forming process; a pattering process of removing a monomolecular film having a rectangular shape; an application process of applying a precursor solution to the first electrode film exposed in the rectangular shape; a piezoelectric film forming process of converting the applied precursor solution into a piezoelectric film; and a second electrode film forming process. Materials of the precursor solution, the first electrode film, and the monomolecular film are adjusted so that the first electrode film is lyophilic and the monomolecular film is lyophobic to the precursor solution. The piezoelectric film forming process includes a drying and thermally decomposing process of drying and thermally decomposing the precursor solution; and a crystallizing process of crystallizing a thermally decomposed piezoelectric material.