A processed Aconiti tuber (Korean name, Kyeong-Po Buja) was extracted with 80% aqueous EtOH, and the concentrated extract was partitioned with EtOAc and water ($H_2O$). From the EtOAc fraction, two flavonoids were isolated through repeated silica gel column chromatographies. From the result of physico-chemical data including NMR, mass spectrometry and IR, the chemical structures of the compounds were determined to be liquiritin (1) and liquiritigenin (2). This is the first study to isolate flavonoids (1) and (2) from the processed Aconiti tuber.