To perform highly accurate joining by preventing bending of a wiring board.

The inkjet head 3 includes nozzles 11 which eject an ink, pressure chambers 41 communicated with the nozzles, ink channels 32, 42, 72, 88 and 92 which supply the ink to the pressure chambers, actuators 60 which give a force for ejecting the ink of pressure chambers from the nozzles, and the wiring board 80 in which wiring lines 87 and 91 connected to the actuators are provided. Insulating layers 70 and 90 of an equal coefficient of thermal expansion are formed on both surfaces of the wiring board.