Abstract: This study was performed to determine the ethanol ratios (30%, 50%, 70%, and 90%) of extraction solvent of Seomaeyakssuk (Artemisia Argyi H.) prepared using different methods (drying at room temperature [D], aging at 60℃ for 7 days after drying [AD], and roasting for 30 min at 160℃ after drying [RD]). The extract yield of the D extracts was lower than that of the AD and RD extracts, but the ethanol concentration of extract solvent did not affect. The L, a, and b values of the D extracts were highest, whereas those of the AD extracts were lowest. No clear trend was observed in the ethanol ratios. The soluble solids, total phenol, total flavonoid, jaceosidin, and eupatilin contents of each extract varied significantly, with RD > AD > D. The soluble solids significantly increased by ethanol ratio of extraction solvent, but other phytochemicals contents of 50% and 70% ethanol extracts were higher than others without affecting the processing methods. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was highest (77.71%) in the 70% ethanol extract obtained from RD. 2,2-azinbis-(3-ethylbenzo-thiazoline-6-sulphonate(ABTS) radical scavenging activity was significantly higher in 30-70% ethanol extract than 90% ethanol extract from RD. The results suggest that the contents of active ingredients and radical scavenging activity of ethanol extracts from Seomaeyakssuk were highest in the RD extract using 50-70% ethanol.