The invention discloses a vibrating mechanism of a dry powder suction device. The vibrating mechanism is characterized by comprising vibrating plates, wherein vibration stirring sheets are arranged at the rear ends of the vibrating plates and can stir a transmission sheet on a quantitative feeding mechanism to make the quantitative feeding mechanism vibrate to achieve smooth material falling when the vibrating plates move front and back. The vibrating mechanism of the dry powder suction device overcomes the defects in the prior art and is simple in structure and capable of achieving smooth material falling.