Abstract: An emission reduction device for cooking fumes produced from smoking, frying and roasting is provided, which includes a purifying-tank shell. One end of the purifying-tank shell is provided with an air inlet and other end of the purifying-tank shell is provided with an air outlet. The device further includes a nebulizer, an ultrasonic coagulating unit, and an electrostatic deposition unit, which are sequentially arranged in the purifying-tank shell from the air inlet to the air outlet. A box body is connected to the air outlet of the purifying-tank shell, the box body is provided with a photocatalytic oxidation unit, a plasma catalytic oxidation assembly and an end filter unit therein. An exhaust port is installed on a rear side of the box body. Two sides of the ultrasonic coagulating unit are each provided with a flow rectifier which is longitudinally and slidably arranged in the purifying-tank shell.