Objectives : This study was conducted to compare antioxidant activity of ratio-related Angelicae Radix and Astragali Radix compositions by DPPH radical scavenging activity. Methods : The species of Angelicae Radix was compared as Angelica gigas, A. sinensis and A. acutiloba. Then various compositions of Angelicae Radix with Astragali Radix were prepared with different ratio. Diphenyl-picryl-hydrazyl (DPPH) radical scavenging activity was measured after 10, 20 and 30 minutes. Each extracts were tested by 1, 5, 10, 50, 100, 500 and 1,000 ${mu}g/ml$ concentrations. Results : The results showed that Angelica gigas, A. sinensis and A. acutiloba scavenged DPPH radical with 66.8, 61.7 and 56.7% in 1,000 ${mu}g/ml$ concentration, respectively. According to this result, Angelicae Radix and Astragali Hadix compositions with 100:0, 10:1, 5:1, 3:1, 1:1, 1:3, 1:5, 1:10 and 0:100 ratio were scavenged DPPH radical with 56.3, 49.9, 61.2, 55.7, 54.7, 55.0, 52.8 ,md 50.2% in 1,000 ${mu}g/ml$ concentration, respectively. The extract of Angelicae Radix and Astragali Radix compositions with 100:0, 10:1, 5:1, 3:1, 1:1, 1:3, 1:5, 1:10 and 0:100 ratio scavenged DPPH radical with the $IC_{50}$ being 85,21, 1016.26, 656.51, 785.67 and 956.74 ${mu}g/ml$ respectively. Conclusion : In conclusion, the extract of Angelicae Radix and Astragali Radix compositions with 1:1 ratio showed dose-dependent DPPH radical scavenging activity.