Abstract: In this study, late harvest white grape pomace was used as material to extract polyphenol. The extraction process of polyphenol from grape pomace was optimized via single-factor test, orthogonal test and variance analysis, and the antioxidant activities of the polyphenols were determined. The results showed that ethanol concentration and extraction temperature had a significant effect on the polyphenol extract. The optimal extraction conditions were as follows: 50% ethanol concentration, extraction temperature 80℃, extraction time 40min. Under the optimized conditions the yield of polyphenol was 3.39 mg/g. The determination result showed that the polyphenol had strong antioxidant activity.