Artemisia japonica is a kind of plant resource used both as medicine and food in China,which is rich in flavonoids.In order to realize the comprehensive utilization of plant resources,the stems and leaves of A. japonica were used as materials.The effects of ethanol volume fraction,ethanol dosage,extraction time and extraction temperature on the extraction content of total flavonoids in A. japonica were analyzed by response surface method,the purification conditions for total flavonoids by macroporous resin were studied,and the antioxidant activity of total flavonoids from A. japonica before and after purification was analyzed.The results showed that the optimal extraction conditions were as follows:ethanol volume fraction 70%,ethanol dosage 20 mL,extraction time 85 min and extraction temperature 40 ℃.AB-8 was an ideal macroporous resin suitable for the separation and purification of total flavonoids from A. japonica. The optimal time of static adsorption and desorption were 2 h and 1.5 h respectively,and the optimal mass concentration of loading sample was 1.2 mg/mL,and the optimal concentration of eluting ethanol was 50%.The antioxidant experiment in vitro showed that the crude extract of total flavonoids from A. japonica(CFAJ) and purified product (PFAJ) with macroporous resin all had good reducing power,and showed strong scavenging ability to ABTS⁺·,DPPH·,·OH,O₂^-·.The flavonoids of A. japonica have the potential and value of exploiting plant flavone resources.