Abstract: Plant phenolics have been recognized largely as beneficial antioxidants that can scavenge harmful active oxygen species. In plant systems, phytophenolics can act as antioxidants. Alpha asarone is one of the phytochemical constituent of essential oil of Acorus calamus and bark of Guatteria gaumeri which exhibits many biological activities. In the present study antioxidant activity of alpha asarone was evaluated using scavenging assays of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radicals, hydroxyl radicals, superoxide anion radicals, chelating ability of ferrous ion, reducing power and inhibition capability of Fe (II)-induced lipid peroxidation. Alpha asarone exhibited strongest antioxidant activities in scavenging DPPH radicals and highest reducing power. Alpha asarone also exhibited best performance in chelating metal ion and inhibiting lipid peroxidation. The results obtained revealed that alpha asarone possess higher antioxidant activity.