Abstract:The microwave -assisted extraction technology and antioxidant activities of flavonoids from grape residues were studied in vitro. On the basis of single factor test，a L9（34）orthogonal experiment methodology was conducted to investigate the influences of four main factors on the yield of flavonoids. The optimum conditions were as follows：60 % （volume fraction）ethanol as the solvent，material-solvent ratio 1：25 （g/mL），microwave time 120 s，microwave power 440 W，and extracted twice. Under such conditions，the yield of flavonoids was 38.64 mg/g. The extraction from grape residues showed significant antioxidant capacity，and activity to removing DPPH·and·OH .