The invention relates to a control valve used for a dust removing system. The control valve is characterized in that the control valve comprises a valve base, a rotating shaft, a butterfly-shaped door, a crank and a swing rotation drive mechanism; the valve base comprises a base plate and a valve pipe; the base plate is provided with a fixed installation hole; the rotating shaft is vertically arranged and penetrates the valve pipe in the radial direction; the upper end of the rotating shaft is supported to the top of the valve pipe through an upper bearing assembly; the lower end of the rotating shaft is supported to the bottom of the valve pipe through a lower bearing assembly; the butterfly-shaped door is arranged in the valve pipe; the shape and the size of the butterfly-shaped door are matched with those of the valve pipe; the butterfly-shaped door is fixedly installed on the rotating shaft; one end of the crank is fixed to a shaft head at the upper end of the rotating shaft; and the other end of the crank is connected with the swing rotation drive mechanism which can drive the rotating shaft and the butterfly-shaped door to rotate by driving the crank to swing, and therefore the control valve is closed to be opened or closed. The control valve used for the dust removing system is compact in structure, reasonable in design, convenient to operate and control, safe, reliable, and capable of effectively controlling and adjusting negative pressure in a negative pressure pipeline and achieving the energy saving and efficiency improving purposes.