The present invention provides an ink jet printer head having a pressure chamber to jet ink by deformation of a piezoelectric member provided in the pressure chamber. The piezoelectric member has an electrode for applying electricity to the piezoelectric member. The present invention provides an insulation layer on the electrode formed by vapor deposition method, which has high adhesion and throwing power. Thus, a plurality of electrodes can be covered by the insulation layer even though these electrodes are not provided on the same plane. Accordingly, the ink jet printer head can be used for a long time in steady without deterioration of the piezoelectric member and the ink in case of using conductive ink like water ink.