L-Ascorbyl Gallate was synthesized from gallic acid and L-ascorbic acid catalyzed by Novozym435 lipase,and its antioxidant activity was determined. The results showed that the conversion rate of gallic acid was up to 82. 7% under the condition of gallic acid 10 mmol,L-ascorbic acid 20 mmol,lipase 0. 25 g,cyclohexanone 20 mL, 50 ℃ and 24 h. The antioxidant tests indicated that L-ascorbyl gallate could efficiently scavenge DPPH radical and hydroxyl radical. The IC 50 of L-ascorbyl gallate to DPPH radical and hydroxyl radical were 9. 97 μmol / L and 2. 45 mmol / L,and IC 50 of L-ascorbic acid to DPPH radical and hydroxyl radical were 23. 55 μmol / L and 5. 14 mmol / L. The antioxidant activity of L-ascorbyl gallate was significantly higher than that of L-ascorbic acid.