A liquid jet head has a head chip including channels and nozzle holes communicating with respective ones of the channels. The channels have sidewalls each provided with a drive electrode. A temperature sensor is configured to detect a temperature of a liquid in the channels. A drive voltage value setting device is electrically connected to the temperature sensor for determining a magnitude of a drive voltage based on the temperature of the liquid detected by the temperature sensor. A control device performs a control operation that applies a drive voltage of the magnitude determined by the drive voltage value setting device to the drive electrodes of the head chip so as to increase a pressure in each of the channels by deformation of the side walls to thereby discharge the liquid in the channels from the respective nozzle holes.