ObjectiveTo establish an HPLC method for simultaneous determination of syringin,schizandrin,deoxyschizandrin and schisandrin B in Shuangwu capsules. MethodsThe HPLC method was employed using a Diamonsil C18 column (200 mm×4.6 mm,5 μm) with a mobile phase of methanol-acetonitrile (1∶1,A) and water (B). The gradient elution program was as follows: 0-5 min,35%-60%A; 5-10 min,60%-70%A; 10-50 min,70%-90%A; 50-90 min,90%A. The flow rate was 1 ml/min. The detection wavelength was set at 220 nm and the temperature was at 35℃.ResultsThe linearity was obtained within the range of 1.28-20.40 μg/ml for syringin (r=0.999 7),6.30-100.80 μg/ml for schisantherin (r=0.999 6),1.20-19.20 μg/ml for deoxyschizandrin (r=0.999 8),and 3.75-60.00 μg/ml for schisandrin B (r=0.999 6). The RSD values of precision were less than 1% for all the four components. The results showed that the samples were stable in the room temperature for at least 24 h. The average recovery rates of syringin,schizandrin,deoxyschizandrin and schisandrin B were 99.47%,102.50%,99.21% and 101.86%,respectively. Conclusion Our method is rapid,easy to perform and accurate; it can be used to control the quality of Shuangwu capsules.