Abstract: A kitchen smoke exhauster includes a driving device, a pressure-control device, a time-control device, an enzyme-containing device and a spray device assembled together therewith. A natural and harmless enzyme composition contained in a reservoir of the enzyme-containing device is atomized via the spray device to well mix with the discharging oil vapor for decomposition under the control of the driving device and the pressure-control device. Thus, it is capable of preventing the air of our environment from pollution of cooking fume and avoiding the cooking oil residues therein to cause the danger of a fire so as to further protect the health of our lives.