Objective: A fast ultra performance liquid chromatographic (UPLC) method for determination of liquiritin and glycyrrhizic acid in Radix Glycyrrhizae and Extractum Glycyrrhizae was established. Method: UPLC was used. The operating conditions were BEH Shield RP18 column (2.1 mm×50 mm

1.7 μm) and gradient elution with acetonitrile (A)-1.0% acetic acid-H2O (B) as mobile phase. The flow rate was 0.5 mL·min-1. The detection wavelength was set at 276 nm for liquiritin and 254 nm for glycyrrhizic acid. The column temperature was maintained at 30℃. Result: The content of liquiritin was linear related to its peak area in the range of 0.01-1.0 g·L-1

and the average recovery of the method was 98.98%;the RSD of precision test was 2.55%. The content of glycyrrhizic acid was linear related to its peak area in the range of 0.03-1.2 g·L-1

and the average recovery of the method was 99.03%;the RSD of precision test was 1.73%. Conclusion: The method can be used for determining the content of liquiritin and glycyrrhizic acid in Radix Glycyrrhizae and Extractum Glycyrrhizae at the same time. The separation of liquiritin and glycyrrhizic acid only needs about 7 min with accuracy and good reliability.