目的 建立一种同时测定中药茯苓中去氢土莫酸、猪苓酸C、3-差向去氢土莫酸和去氢茯苓酸等4种三萜酸的方法，为其质量控制提供检测手段。方法 采用Agilent Zorbax SB-C₁₈色谱柱（3.0 mm×100 mm，3.5 μm，以乙腈-0.05%磷酸水溶液为流动相进行梯度洗脱，流速为0.6 mL·min-1，紫外检测波长为243 nm，柱温为40 ℃。结果 在以上色谱条件下，供试品溶液中的4个被分析物均与干扰成分完全分离，在4.48~143、1.38~44.2、3.20~102和7.72~247 μg·mL-1范围内线性关系良好（r2≥0.999 8，RSD<3.11%（n=6，制备的样品溶液在48 h内测定各三萜酸峰面积RSD不超过1.31%，4个茯苓三萜酸的平均加样回收率介于98.8%~102%（RSD≤2.30%。结论 本方法可用于茯苓药材中以上4种三萜酸的含量测定。

OBJECTIVE To establish a RP-HPLC method for the determination of four triterpenes including dehydrotumulosic acid， polyporenic acid C， 3-epidehydrotumulosic acid and dehydropachymic acid in Poria. METHODS The determination was performed on an Agilent Zorbax SB-C₁₈ column (3.0 mm×100 mm， 3.5 μm at 40 ℃ during the elution. The mobile phase composed of acetonitrile and water containing 0.05% H₃PO₄ (v/v under gradient elution， which was driven at a constant flow rate of 0.6 mL·min-1. The detection wavelength was at 243 nm. RESULTS Under the above chromatographic conditions， all four analytes were completely separated from the interferent in the tested sample solution. The linearities of the analytes were good (r2≥0.999 8 within the ranges of 4.48-143， 1.38-44.2， 3.20-102 and 7.72-247 μg·mL-1， respectively. RSDs of repeatability test were less than 3.11% (n=6. In addition， RSDs of peak areas were no greater than 1.31% of the stability (48 h， and the average recoveries of four triterpenes were in the ranges of 98.8%-102%（RSD≤2.30%. CONCLUSION The established method can be used for the determination of the four triterpenes in Poria.