Abstract:Objective: To compare the vitro antioxidant components of Shengmaisan (SMS) and Yiqi Fumai sterile powder (YQFM). Method: The scavenging activities of SMS and YQFM for ABTS·+ radicals was determined by HPLC-ABTS-DAD. Result: SMS had a good effect of scavenging ABTS·+ radicals with the saccharides, amino acids and lignans as potential active components responsible for its scavenging activities. The scavenging activities of YQFM were relatively weak. Conclusion: Although SMS and YQFM are the different preparations for the same complex prescription, they have large differences in directly scavenging radicals.