Abstract: The present study was to investigate the composition characteristics and free radical scavenging activity of wheat bran feruloylatedgl ycosides with high polymerization degree.Feruloylated glycosides of wheat bran was prepared by acid hydrolysis method,and then the component of F1 with high polymerization degree was purified and isolated by Amberlite XAD-2 macroporous resin and Sephadex LH-20 gel chromatography.The average polymerization degree of F1 was determined by the acetylacetone method;phenolic acid (ferulaic acid) were detected by high performance liquid chromatography (HPLC);sugar composition was examined by gas chromatography (GC);and the glycosidic linkage was measured by infrared spectroscopy (IR).Moreover,the scavenging capacity of F1 on DPPH and·OH was detected by using the UV spectrophotometry method and compared with ferulic acid standard.The feruloylated glycosides of wheat bran with different polymerization degree were obtained by separation and purification.The composition analysis of F1 with high polymerization degree showed that esterified ferulic acid,arabinose and xylose with β(1-4) pyranoside bond were contained,and the average polymerization degree was 10.9.Furthermore,the scavenging capacity of F1 on·OH and DPPH had positive correlation with the concentration,in which the·OH scavenging ability of F1 was better than that of free ferulic acid.Briefly,the component of F1 with high polymerization degree was feruloylated arabinoxylan,which was composed of ferulic acid and arabinoxylan.F1 has better free radical scavenging capacity on DPPH and·OH,which will have a wide research and development prospect.