对膜荚黄芪毛状根中６种异黄酮成分进行了反相高效液相色谱法测定。色谱柱为ＮｕｃｌｅｏｓｉｌＣ１８柱，流动相为甲醇—水（３∶２和３∶１，ｖ／ｖ），检测波长为２５４ｎｍ和２８０ｎｍ。６种异黄酮成分为：１０羟基３，９二甲氧基紫檀烷，（３Ｒ）８，２’二羟基７，４’二甲氧基异黄烷，芒柄花素（７羟基４’甲氧基异黄酮），８，３’二羟基７，４’二甲氧基异黄酮，２’羟基３’，４’二甲氧基异黄烷７Ｏ葡萄吡喃糖甙，毛蕊异黄酮（７，３’二羟基４’甲氧基异黄酮）。异黄酮浓度在２５～１２５μｇ范围内与峰面积有良好的线性关系；加样回收率为９６４７％～１０３３３％；精密度试验相对标准偏差为２５７％～６５２％；测得黄芪毛状根中６种异黄酮成分的含量在００００５％～０００６５％之间。 Six kinds of isoflavones in hairy roots of Astragalus membranaceus were determined by RP-HPLC. The column was a Nucleosil C18 column with a mobile phase of methanol-water (3:2 and 3:1, v/v) and detection wavelengths of 254 nm and 280 nm. The 6 kinds of isoflavones were: 10hydroxy3,9dimethoxyarylene, (3R)8,2′dihydroxy7,4′dimethoxyisoflavan, formononetin (7-hydroxy-4’-methoxy isoflavone), 8,3’-dihydroxy-7,4’-dimethoxyisoflavone, 2’-hydroxy-3’, 4’-dimethoxy Isoflavan 7-O grape pyranose, calycosin (7,3 ’-dihydroxy 4’-methoxy isoflavone). There is a good linear relationship between the isoflavone concentration and the peak area in the range of 25～125μg; the recovery of the sample is 9647%～10333%; the relative standard deviation of the precision test is 257%～6. 52%; The content of six kinds of isoflavones in the hairy root of Scutellaria baicalensis was measured between 00005% and 00065%.