Abstract: Orthogonal experimental design was applied to optimize the extraction process of total flavonoids from Iberis amara using an ultrasonic- assisted extraction method in this study. The effects of ethanol concentration,extraction time,solid- to- liquid ratio and ultrasonic power on the extraction yield of total flavonoids were investigated by single- factor experiment,and then the extraction conditions were optimized by orthogonal experimental design. The results displayed that the ethanol concentration was the most key factor,followed by extraction time,solid- to- liquid ratio and ultrasonic power,in turn.The best extraction conditions were obtained as follows: ethanol concentration 85%,solid- to- liquid ratio 1 ∶ 70,extraction time 15 min and ultrasonic power 100 W.Under these optimized conditions,the yield of total flavonoids from Iberis amara was 2.456%.This study offered not only a reference standard for industrial applications,but also has a promising prospect and value for widely exploitation and utilization of Iberis amara resource.