Abstract: To improve the extraction efficiency and utilization of peanut oil, the ultrasonic-assisted aqueous enzymatic method was used to extract peanut oil. The effects of ultrasonic power, treatment time, temperature, solid-liquid ratio, and enzyme dosage on the extraction rate of peanut oil were studied. The extraction conditions were then optimized by response surface methodology. The fatty acid composition, acid value, peroxide value and antioxidant capacity of peanut oil were finally analyzed. The optimal conditions for peanut oil extraction were as follows: material to liquid ratio of 1∶5 g/mL, cellulase dosage of 1.0%, ultrasonic power of 247 W, 41 min and 51 ℃. Under these conditions, the oil extraction rate reached 92.64%±0.73%. A total of 8 fatty acids were detected in peanut oil, among which oleic acid exhibited the highest concentration at 40.44%±0.57% followed by linoleic acid 36.97%±0.05%. The acid value and peroxide value were determined to be (0.38±0.04) mg/g and (0.15±0.00) g/100 g, respectively. Additionally, the DPPH and ABTS free radical scavenging rates were 64.82%±2.51% and 82.56%±6.47%, respectively. Ultrasonic-assisted aqueous enzymatic method effectively shortened the processing time and reduced the dosage of enzyme. The obtained peanut oil contained high content of unsaturated fatty acids and showed excellent antioxidant capacity.