Objective:To study on antioxidant activity of effective components in Acanthopanacis Senticosi Radix et Rhizoma Seu Caulis roots. Method: Contents of total saponins and total flavonoids were determined by UV.Antioxidant activity of effective components in Acanthopanacis Senticosi Radix et Rhizoma Seu Caulis roots were conducted with superoxide anion free radical scavenging method

hydroxyl free radical scavenging method

DPPH scavenging method and FRAP method. Result: Different effective components in a certain concentration range had some antioxidant activities.When the concentration increased

antioxidant ability enhanced.Clearance of 30% ethanol eluted site on O2-·was(91.61±2.59)% at the concentration of 20 g·L-1.Clearance of 30% ethanol eluted site on·OH was(90.29±2.06)% at the concentration of 1.0 g·L-1.Clearance of 30% ethanol eluted site on DPPH was(84.45±0.14)% at the concentration of 0.7 g·L-1.FRAP value of 30% ethanol eluted site was 3474±36.84 at the concentration of 1.0 g·L-1. Conclusion: All the effective components of Acanthopanacis Senticosi Radix et Rhizoma Seu Caulis roots have a certain antioxidant activity.Antioxidant activity of 30% ethanol eluted site is the highest.