In order to separate and prepare the antioxidant peptide, this article used central composite design and response surface to optimize the extraction process of antioxidant peptide.Taking DPPH radical scavenging rate as response, analyzed the influence of solid-liquid ratio, hydrolysis time and enzyme concentration on the preparation of antioxidant peptides. Got the peptide with antioxidant activity after Sephadex G-50、G-25and G-10 used to separate and purify it, and then measured the DPPH radical scavenging, Superoxide anion radical scavenging activity, ABTS radical scavenging, hydroxyl radical scavenging activity and metal ion chelating activity. The optimum extraction conditions as follows: Solid-liquid ratio was 1:3, extraction time 6h and enzyme concentration 6500U/g at the same time the DPPH radical scavenging was 66.89%. The IC50 of the DPPH radical scavenging, Superoxide anion radical scavenging activity, ABTS radical scavenging, hydroxyl radical scavenging activity were 0.073g/L、0.989 g/L、0.192 g/L and 1.261 g/L, respectively. The IC50 of metal ion chelating activity was 6.505 g/L, the molecular weight was 175.00 Da.