An ink-jet head includes a channel unit and a piezoelectric actuator. The channel unit has a plurality of plates made of metal and including a cavity plate which is made of metal and in which a plurality of pressure chambers are formed and a supply plate which is made of metal and in which holes communicating with the pressure chambers respectively are formed, and the plates are diffusion-bonded with each other. The piezoelectric actuator has a vibration plate which is diffusion-bonded with the cavity plate. A groove is formed in a partition wall defining the pressure chambers or in an area overlapping the partition wall of the vibration plate, the cavity plate, and the supply plate. There is provided a liquid jetting head in which air hardly remains in the pressure chambers, and deterioration of jetting performance by the air is suppressed.