The invention discloses a novel full-automatic sodium carbonate dry powder adding system. The system comprises a powder bin, a stirring and feeding coupling device, a pneumatic gate valve, a conveyingdevice and a dosing point. Before the dry powder adding system starts to work, sodium carbonate powder is conveyed to the powder bin through pneumatic conveying equipment on a bulk tank truck until the powder bin is full, a PLC controls the pneumatic gate valve and a automatic dosing valve to be opened, and a frequency conversion motor of the stirring and feeding coupling device is controlled towork; dry powder flowing out from the bottom of the powder bin enters the conveying device and is added to the dosing point through the conveying device, and after dosing is finished, the pneumatic gate valve, the automatic dosing valve and the frequency conversion motor of the stirring and feeding coupling device are controlled to be closed. The full-automatic sodium carbonate dry powder adding system is simple in structure, safe, reliable, convenient to use and low in cost. In the system, a cavity or an arch bridge formed at a conical outlet of the powder bin is effectively destroyed throughthe stirring and feeding coupling device, so that the dry powder is discharged smoothly.