In order to improve the extraction efficiency of feruloyl oligosaccharides( FOs) from defatted rice bran using cellulase hydrolysis,single factor experiments and response surface analysis were employed to optimize the enzymolysis. The results suggested that the optimal extraction conditions were as follows: pH 4. 16,reaction temperature 55 ℃,enzyme addition amounts 0. 29 mg / g,and reaction time 11. 76 h. Under these conditions,the extraction amount of FOs reached 28. 48 μmol / g. And the scavenging effect of FOs on the DPPH · and · OH; EC50 were 0. 750 5 mg / mL and 3. 270 5 mg / mL,respectively.