According to one embodiment, an inkjet head includes a plurality of actuators on a substrate in a row and spaced from each other, each actuator extending from the substrate to form a chamber space between each adjacent pair of actuators in the plurality of actuators, a flow passage block including a frame portion surrounding an outer periphery of the plurality of actuators and a blocking portion having protrusions sealing both ends of the chamber spaces between every other adjacent pair of actuators along the row, and a common ink chamber above the flow passage block and in fluid communication with the chamber spaces between any adjacent pairs of actuators not sealed at both ends by the blocking portion with a plurality of chamber spaces.