The invention provides a smoke exhaust ventilator and a control method of the smoke exhaust ventilator. The smoke exhaust ventilator comprises a smoke exhaust ventilator body and a refrigerating system arranged on the smoke exhaust ventilator body. The smoke exhaust ventilator body comprises an exhaust cavity and a refrigerating cavity, and the refrigerating cavity is provided with an air outlet. The refrigerating system comprises a compressor, an evaporator and a condenser. The evaporator is arranged in the refrigerating cavity. The condenser is a water-cooled heat exchanger. A cooling water cavity of the water-cooled heat exchanger is provided with a cold water connector connected with a cold water pipeline. According to the smoke exhaust ventilator and the control method of the smoke exhaust ventilator, the condenser is arranged into the water-cooled heat exchanger, cold water is introduced into the cooling water cavity of the water-cooled heat exchanger, the heat efficiency of the condenser can be effectively improved, and the refrigerating effect is improved.