The invention discloses a device and method for processing ultrafine nickel powder through high speed rotating airflow. An air compressor is communicated with one end of an air storage tank, the other end of the air storage tank is respectively connected with a pneumatic cracker and a back-blowing collection kettle, a feeder is connected with the pneumatic cracker, the pneumatic cracker is connected with the back-blowing collection kettle, the back-blowing collection kettle is connected with an induced draft fan, and the induced draft fan is connected with a tail gas processing device. The processing method includes the steps that first, air is led into the air compressor and compressed into high-pressure airflow to be introduced into the air storage tank for standby use; second, ultrafine nickel powder is fed into the pneumatic cracker through the feeder, meanwhile, high-pressure airflow is introduced into the pneumatic cracker, and aggregated powder is crashed; third, the crashed powder enters the back-blowing collection kettle; fourth, high-pressure airflow collection having collision and friction with powder particles is exhausted into the tail gas processing device through the induced draft fan. The device and method have the advantages that the hard aggregation problem of powder can be effectively solved, and the ultrafine nickel powder has good surface cleanliness and dispersity.