The centrifugal exhaust fan consists of blades, motor, frame, protective net, supporting frame, shutter, centrifugal system and other components. The shutters are automatically opened after starting. After shutting down, the shutters are automatically closed to prevent outdoor dust and foreign matter from entering, and also to avoid the influence of rain and snow and downwind. The frame is made of advanced processing technology with high accuracy. The standard zinc layer is highly corrosion-resistant. The use of 1.5/0.8mm hot-dip galvanized plate not only increases the service life and intensity of shutters, but also increases the quality of the whole machine and improves the stability in operation.