Abstract: The raw material was sea buckthorn lyophilized powder,and the ultrasonic-assisted and ethanol solvent method was used to extract sea buckthorn polyphenols. The extraction conditions were optimized by single-factor test and response surface test. The macroporous resin was used for static adsorption-analysis test of sea buckthorn polyphenols. In vitro antioxidant tests were carried out on sea buckthorn polyphenols before and after purification. The test results showed that when the ratio of liquid to solid was 1∶24 (g/mL),the volume fraction of ethanol was 49%,the extraction time was 52 min,and the extraction temperature was 48 ℃,the extraction amount of polyphenol was the largest,reaching(8.61±0.25)mgECGC/g. The AB-8 was identified as suitable macroporous resin for purification of sea buckthorn polyphenols. The semi-inhibitory concentrations(IC₅₀)of polyphenols from sea buckthorn on DPPH free radical before and after purification were 713.22 and 142.53 μg/mL,and The semi-inhibitory concentrations(IC₅₀)of polyphenols from sea buckthorn on ABTS free radical before and after purification were 61.92,8.68 μg/mL. The results showed that the polyphenols from sea buckthorn after purification had good antioxidant capacity.