The roots of Dipsacus asper are used in traditional Chinese medicine as an analgesic, enhancement of liver activity, an anti-inflammatory agent and the treatment offractures. In order to investigate the antioxidative activity, Dipsaci Radix was extracted with MeOH and fractionated with CHCl3, EtOAc, BuOH and water. MeOH ex. and its solvent fractions were determined on the free radical scavenging activity by DPPH method and antioxidative activity on low density lipoprotein oxidation. The EtOAc and BuOH fractions showed antioxidative activities and from their fractions, two compounds were isolated and identified as hederagenin 3-O-α-L-arabino pyranoside (compound 1) and O-α-L-arabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl (1→6)-β-D-glucopyranosyl ester (compound 2). Saponin glycoside, compound I showed anti-oxidative activity.