A liquid jet head includes a piezoelectric body substrate on which ejection grooves penetrating from an upper surface to a lower surface and non-ejection grooves open on the lower surface are alternately arranged in a reference direction and form a groove row, a cover plate that includes a liquid chamber communicating with the ejection grooves is bonded on the upper surface of the piezoelectric body substrate, and a nozzle plate that includes nozzles communicating with the ejection grooves is bonded on the lower surface of the piezoelectric body substrate. Common drive electrodes are installed on side surfaces of the ejection grooves, which are on the lower-surface side from nearly ½ the depth of the ejection grooves, and individual drive electrodes are installed on side surfaces of the non-ejection grooves, which are on the lower-surface side from nearly ½ the depth of the non-ejection grooves.