To provide a speaker wherein the oxidation of an external electrode is prevented and a contaminant eliminating function is provided.

A speaker 10 includes a spherical shell-like sounding body 11. The sounding body 11 is composed of a spherical/shell-like vibrator 12, an external electrode 13 formed in the outer surface of the vibrator 12 and an internal electrode 14 formed in the inner surface of the vibrator 12. A cover film 15 is formed in the outside of the external electrode 13. The sounding body 11 is mounted on a cylindrical horn 16. The vibrator 12 is made of a piezoelectric ceramic such as PZT, and polarized in a thickness direction. The external and internal electrodes 13 and 14 are made by burning conductive paste mainly containing silver. The cover film 15 is formed by doping the fine particles of titanium oxide with chromium ion by means of ion implantation, dispersing the doped titanium oxide particles in organic solvent, coating the same on the outside of the external electrode 13 and performing heat treatment.