High-speed countercurrent chromatography (HSCCC) is a continuous and efficient liquid-liquid chromatography.Because there is no solid support,the separation of substances are achieved based on the different partition coefficients between the two-phase immiscible liquid [1-2].Thus it can avoid the sample loss,inactivation and denaturation,which are caused by the irreversible adsorption of the solid stationary.The recovery of the sample reflects its original properties.Therefore,HSCCC is suitable for the isolation of active ingredients in natural products.In this work,dextran gel (Sephadex LH-20) is applied to separate and enrich the target substances of the ethyl acetate extracts of the astragalus,and then HSCCC separation process is developed,with the ARIZONA solvents system,to purify 50% and 70% methanol fir actions.The results show that four components are isolated from 50% methanol fraction under the following operation conditions:the proportion of the solvents (n-hexane/ethyl acetate/methanol/water) is 1:2:2.4:1.2 (v/v),flow rate is 2 ml/min,rotation speed is 900 r/rain,and operating temperature is 25±1℃.The purity of them reach to 93.21%、 98.42%、 99.17%、99.26%,respectively.In the 70% methanol fraction,two components are obtained under the same experiment conditions except that the proportion of the solvent system (n-hexane/ethyl acetate/methanol/water) is changed to 1:2:1.2:1 (v/v),and the purity of them are 99.95%,97.62%,respectively.