Abstract: In order to obtain the optimum extraction conditions of total flavonoids from Coriandrum sativum L., the factors affecting the extraction rate of total flavonoids were evaluated by Plackett-Burman Design firstly.Three main factors including the ratio of solvent to sample, the microwave extraction temperature, and the ethanol concentration were selected. These factors were optimized by Response Surface Methodology ( RSM) , the extraction rate of total flavonoids was chosen as the response. The results showed that the optimal extraction conditions were as follows: the ratio of solvent to sample was 35∶1, the microwave extraction temperature was 80℃, and the ethanol concentration was 67%.Under the optimal extraction conditions, the predicted value of the rate of total flavonoids was 1.33%, the measured value was 1.31%, and the deviation was 1.30%.The result indicated that the extraction technology of total flavonoids from C.sativum could be optimized well by the combination of Plackett-Burman Design and RSM.