PURPOSE: To provide an ink jet head in which a life of the head is obtained and a cost is reduced in the head in which a vibrating plate is formed of a titanium material.

CONSTITUTION: An ink jet head comprises a nozzle plate 12 having at least one nozzle 9 for injecting particle of ink 6, a piezoelectric element 8 corresponding to the nozzle 9, a vibrating pate 14 formed of a titanium material and having a protrusion 15 in contact with one end face of the element 8, and a pressure chamber 13 for forming an opposed surface of the plates 12 and 14, formed corresponding to the nozzle 9 and fully filled with ink 6. A voltage is applied to the element 9 to vibrate the plate 14 by a displacement due to electrostriction of the element 8 to generate a pressure in the chamber 13, thereby injecting particles of the ink from the nozzle 9 by the pressure.