Abstract: Antioxidant peptide from agaricus bisporus was modified by Maillard reaction using reducing power as an inspected indicator.The effect of four main factors including kind of carbohydrate, volume fraction, pH value and time on Maillard reaction were studied by using single factor analysis method.On this basis, the optimal technology for Maillard reaction modification of antioxidant peptide from agaricus bisporus was obtained by orthogonal experiment.Experimental results showed that the best technology for Maillard reaction modification of antioxidant peptide from agaricus bisporus were as following:reactant of fructose, volume fraction of 4:1, pH11.0, 150min, the reducing power of modified antioxidant peptide by Maillard reaction on this condition was about 5 times of original antioxidant peptide.This suggests that the Maillard reaction might be served as an effective approach to improve antioxidant activity of antioxidant peptide.