Taking the mung bean sprouts after drying as raw materials, the changes in the extraction amount, antioxidant activity and physical properties of mung bean sprouts polyphenols after airflow ultrafine crushing treatment were compared. The results show that the best conditions for ultrafine pulverization of air flow were as followed: pressure 0.5 MPa and speed 5 000 r/min. Compared with conventional crushing, the extraction of mung bean sprouts polyphenols increased by 10.74%. In addition to the reduction of DPPH free radical scavenging ability, the removal ability of mung bean sprouts polyphenols to ABTS⁺ free radicals and hydroxyl free radicals increased by 2.8% and 13.2%, respectively. The water content, water activity, and particle size were significantly reduced, and the specific surface area, solubility, and bulk density were increased, indicating that the air flow ultra-fine crushing had improved the effective utilization of mung bean sprout powder to a certain extent.