A mist generator device includes a mist generation unit that generates mist from a liquid. A mist flow passage is connected to the mist generation unit. The mist from the mist generation unit flows through the mist flow passage. A tubular mist nozzle releases the mist, which is supplied from the mist generation through the mist flow passage, out of the mist generator device. The mist nozzle includes a mist entrance, a mist exit, and an inner constriction located at an inner side of the mist nozzle. The inner constriction includes a step that decreases an inner diameter of the mist nozzle from the mist entrance toward the mist exit.