The invention discloses a kitchen ventilator and a volute assembly thereof. The kitchen ventilator comprises a steam generator, a volute, a wind wheel and a steam spraying pipe. The volute is providedwith a steam channel, and a steam inlet of the steam channel communicates with a steam outlet of the steam generator. The wind wheel is arranged in the volute. A steam inlet of the steam spraying pipe communicates with a steam outlet of the steam channel. The steam spraying pipe is matched with the wind wheel so as to spray steam to the wind wheel. According to the kitchen ventilator of the embodiment, the wind wheel can be cleaned, the volute can be cleaned as well, and accordingly the beneficial effects that exhaust is smooth, noise is low, energy consumption is low, and the service life ofa motor is long are achieved.