Objective Using the fruits of Prunus cerasifera as raw materials, this study aimed to optimize the preparation process of polyphenols and evaluate their antioxidant activity.Methods The optimal extraction conditions for polyphenols from P. cerasifera were determined using ultrasound-assisted compound enzyme extraction, optimized through single-factor experiments and a Box-Behnken response surface design. Macroporous adsorption resin was employed for the enrichment and purification of the polyphenols. The DPPH radical scavenging ability, ABTS? radical scavenging ability, and total antioxidant capacity of the polyphenols before and after purification were evaluated.Results The optimal extraction conditions were as follows: pectinase to cellulase mass ratio of 1∶2, enzyme addition of 1.5%, solid-liquid ratio of 1∶29 (g/mL), ultrasonic time of 37 min, and ultrasonic temperature of 60 ℃, resulting in a maximum polyphenol yield of (12.82±0.43) mg/g. HPD-300 was identified as the optimal purification resin through static adsorption-desorption screening, with adsorption equilibrium reached in 2 hours and desorption equilibrium in 0.5 hours. The optimal purification parameters using HPD-300 resin were as follows: sample concentration 100 mg/mL, sample volume 180 mL, flow rate 120 mL/h, ethanol concentration 60%, and eluent volume 210 mL. After purification with HPD-300, the IC₅₀ values of the polyphenols for DPPH and ABTS? radicals were 43.16 times and 16.00 times higher than those before purification, respectively, and the total antioxidant capacity was significantly enhanced.Conclusion The combination of ultrasound-assisted compound enzyme extraction and purification using HPD-300 macroporous adsorption resin enables efficient enrichment and purification of polyphenols from P. cerasifera, and significantly improves their antioxidant activity.