OBJECTIVE:To provide more effective means for the quality control of Paeonia suffruticosa by improving the method for simultaneous determination of paeoniflorin and paeonol in P.suffruticosa.METHODS:Agilent ZORBAX Eclipse XDB C18(250 mm×4.6 mm,5 μ m) column was used with mobile phase consisted of methanol-water(gradient elution) at the flow rate of 1.0 ml/min.The detection wavelength was 230 nm for paeoniflorin and 274 nm for paeonol.RESULTS:The linear range of paeoniflorin was 0.060 33-1.206 6 μg and that of paeonol was 0.200 4-4.008 0 μg(r=0.999 9).RSDs of precision test,reproducibility test and stability test were all lower than 2%.The average recoveries were 99.49% and 98.66% with RSDs of 2.0% and 1.8% respectively(n=6).CONCLUSION:The modified method removes phosphate corrosion for chromatographic column.The method is simple,rapid and accurate,and can be used for the qualitative analysis of paeoniflorin and paeonol in P.suffruticosa and its preparations.