Abstract: An ink jet head includes a pressure chamber connected to a nozzle, an actuator configured to cause liquid in the pressure chamber to be ejected from the nozzle by deforming a wall of the pressure chamber, and a drive circuit configured to apply voltage to the actuator to drive the actuator. When a droplet of the liquid is ejected from the nozzle, the voltage applied to the actuator is changed from a first value to a second value that causes the pressure chamber to expand, and then changed from a third value that is equal to the second value or between the first value and the second value to the first value after a time period ?, which is a primary natural oscillation period of the actuator when the pressure chamber and the nozzle are filled with the liquid.