A liquid jet head has a nozzle plate with nozzle holes for ejecting a liquid. A wall portion surrounding the nozzle plate has an opening opposed to the nozzle holes. An opening and closing mechanism is configured in an open state to open the opening of the wall portion to expose the nozzle holes to an exterior of the head, and in a closed state to close the opening of the wall portion to form a closed space between the wall portion and the nozzle plate. A suction flow path has on one end side a suction port opening below the nozzle holes, and another end side is connected to a suction portion that evacuates the closed space to convert the closed space to a negative pressure chamber, thereby supplying the liquid to the nozzle holes. An atmosphere release portion switches between the open and closed states of the mechanism.