Obiective: In the study, corn bran powder was used as raw material, and the cell wall was destroyed by ultrasonic vibration and enzymatic hydrolysis, so that corn bran polysaccharide could be dissolved more fully. Methods: The extracted amount of polysaccharide was taken as the index, response surface test optimization was carried out on the basis of single factor test. And the antioxidant activity of corn bran polysaccharide was determined. Results: The optimal extraction process of corn bran polysaccharide was obtained as follows: mass ratio of cellulase to pectinase 2∶1, enzyme dosage was 2% of the quality of corn bran powder, enzymatic hydrolysis time 50 min, ultrasonic treatment 15 min, and solid-liquid ratio （m_{corn bran powder}∶V_{distilled water}） 1∶15 （g/mL）. At this time, the average amount of extracted corn bran polysaccharide was 23.36 μg/g. The extracted corn bran polysaccharide had a certain total reducing capacity, scavenging DPPH free radical and hydroxyl radical ability, and it increased with the increase of mass concentration, when the mass concentration of corn bran polysaccharide sample was 0.2～1.0 mg/mL. Conclusion: Ultrasound-assisted enzymatic method could extract more polysaccharides than single enzymatic method, and the extract could maintain efficient antioxidant capacity.