Abstract:Objective: To establish a high performance liquid chromatographic method (HPLC) for simultaneous determination of rubrofusarin gentiobioside, casside, cassiaside C in Cassia obtusifolia. Method: The HPLC with Dionex Acclaim C18(4.6 mm×250 mm, 5 μm) column was used, acetonitrile-THF-1% acetic acid (17 :2 :81) was used as a mobile phase, with flow rate of 1 mL·min-1, column temperature at 30 ℃ and detection wavelength at 278 nm. Result: Rubrofusarin gentiobioside, casside, cassiaside C showed good linearity (r=0.999 9) in the range of 0.218-1.09, 0.188-0.94, 0.200-1.000 μg, regressive equation were Y=54.017X-0.344 6 (r=0.999 9),Y=78.63X-0.354(r=0.999 9),Y=74.098X-0.433 5 (r=0.999 9)respectively;the average recoveries of the method were 98.43%, 101.89%, 102.46%, RSD were 1.75%, 1.10%, 1.15%. Conclusion: The method was proved to be simple, rapid, sensitive, precise, reliable and repeatable. It can be applied to the quality control of Semen Cassia.