Abstract In this study, an ultrasonic-assisted enzymatic extraction (UAEE) method was proposed and optimized for the extraction of polysaccharides (CEPs) from Epimedium leaves. In the first step, the optimization of enzyme mixtures for the hydrolysis of Epimedium leaves was carried out by the combined use of one-factor-at-a-time method and orthogonal array design. Subsequently, the optimization of extraction parameters was done using Box-Behnken design with response surface methodology. The results showed that the influence of the dosage of enzymes on the extraction yield of CEPs was in the following order: cellulose > pectinase > papain > α-amylase, and the optimal combination found were papain 50 U/g, pectinase 250 U/g, cellulase 200 U/g and α-amylase 100 U/g. The optimal extraction parameters were determined as 46.8 ℃, 42.3 min, 4.3 and 311 W for temperature, time, pH, and ultrasonic power, respectively. Under these conditions, the experimental yield of CEPs was 5.98%, which was well in close agreement with the value (6.2%) predicted by the proposed model. Three major fractions (EPs-1, EPs-2 and EPs-3) from the CEPs were purified by DEAE-Sepharose fast-flow and Sephadex G-100 column chromatography. The antioxidant activities of the three fractions were evaluated by 1,1-diphenyl- 2-picrylhydrazyl (DPPH) radical, hydroxyl radical and superoxide anion racial scavenging capacity assays, and ferricreducing antioxidant power (FRAP) assay in vitro. It was indicated that UCEE could be an effective and environmentfriendly technique for extracting active ingredients from plant materials. All the three polysaccharides exhibited significant antioxidant activities in a dose-dependent manner. These results suggested that Epimedium polysaccharides could be explored as potential antioxidants for use in functional foods or medicines.