Abstract: The process conditions of ultrasonic-assisted ethanol extraction of resveratrol in peanut roots and the purification of resveratrol by macroporous resin were studied. The effects of ethanol concentration, ultrasonic power, ultrasonic time and solid-liquid ratio on the extraction rate of resveratrol from peanut root were investigated. After optimization by single-factor experiments and response surface methodology, a promised yield of resveratrol (175.53±1.57 μg/g) was obtained under optimal conditions: Ethanol concentration 90%, ultrasonic power 290 W, ultrasonic time 12 min, and solid-liquid ratio 1:38 (g:mL). Analysis of variance was performed to find that the effects of ultrasonic time, ultrasonic power and ethanol concentration on the extracted content of resveratrol reached the significance level (P<0.05). Under the best conditions, the resin was H103, sample concentration 201.13 μg/mL, sample loading rate 1.0 mL/min, sample loading volume 120 mL, elution solvent 90% ethanol, elution flow rate 1.0 mL/min, elution volume 160 mL, after one treatment, the content of resveratrol in the product was 49.19%±0.81% and the RSD value was 1.65%. The ultrasonic-assisted extraction of resveratrol and the preliminary purification of resveratrol by macroporous resin would be promised and reliable, which would provide a reference for the rational development and comprehensive utilization of peanut roots and the standardization and industrial production of natural resveratrol.