Abstract: The degree of hydrolysis used as response value,the enzymatic hydrolysis condition of Maca protein which prepare for Maca peptide was optimized with orthogonal test experiment,and·OH,DPPH and O₂^-·scavenging activities were tested for antioxidant activity evaluation.The results showed that the most suitable enzyme was alkaline protease,alkaline protease optimal preparation conditions of Maca peptide were as follow:time 4 h,pH10.5,temperature 55℃,the amount of enzyme 1.6×10⁴ U/g. Under this condition, the preparation of Maca polypeptide hydrolysis was(31.55%±0.74%). Scavenging radicals ability of double dilution of maca alcohol was maximum, the scavenging rate of DPPH was 94.44%, the scavenging rate of·OH was 85.05%,the scavenging rate of O₂^-·was 53.85%.IC₅₀ values of Maca peptide scavenged DPPH,·OH and O₂^-·were 0.85, 0.44,0.86 mg/mL,and its antioxidant capacity increased with the concentration.In addition,the four amino acid compositions of Maca peptide:Tyr, his, Lys, Pro, their contents were 16.98%, the amino acid composition have a certain relationship with antioxidant activity.The results showed that both of Maca alcohol and Maca peptide have antioxidant activity.