The invention relates to a full-automation powder quantitatively feeding device which comprises a box body, a vibration feeding device, a weighing device and a feeding device body. The full-automation powder quantitatively feeding device is characterized in that the vibration feeding device comprises a material barrel, a feeding pipe, a material groove and a vibration feeder. The material barrel is arranged above the box body, one end of the feeding pipe is connected with a lower outlet end of the material barrel and the other end of the feeding pipe penetrates into the box body through an opened hole above the box body. A sensor is arranged on the wall of the feeding pipe and controlled by a PLC. The material groove is formed below the feeding pipe and installed in the vibration feeder. The weighing device is located below an outlet of the material groove. The feeding device body is located below the weighing device. The full-automation powder quantitatively feeding device is high in feeding speed and accurate in weighing.