Mulberry enzyme is adding lactic acid bacteria,yeast and other probiotics in the mulberry juice after fermentation under certain conditions,which is rich in a variety of nutrients.The biological activity of mulberry enzyme is tested and studied.Firstly,the concentration of polyphenols and proanthocyanidins in mulberry enzyme is determined by ultraviolet detection and liquid phase detection.The results are 1.615 × 103 mg/L and 5.344 mg/mL respectively.Besides,the antioxidant activities of the mulberry enzyme are studied.The results show that mulberry enzyme has a strong DPPH · free radical and ABTS · free radical scavenging effect,the enzyme activity of SOD is 240 U/mL,which is a functional fermented beverage with good taste,rich nutrition and beauty-maintain effect.