Objective: To compare the contents of licorice glucoside and glycyrrhizic acid in Sini Decoction processed by traditional extraction method

water extraction and alcohol precipitation method included in Pharmacopoeia and the single herb separately extracted then combined method. Method: To determine the the contents of licorice glucoside and glycyrrhizic acid was determined by three extraction method.Separation was carried out on C18 column. A linear solvent gradient elution is used and solvent A was acetonitrile

and solvent B is water containing 0.05% phosphoric acid. The flow rate was 1.0 mL·min-1 at 25 ℃ and the detector was set at 237 nm. Result: The content of licorice glucoside was 2.57 mg·g-1 in the traditional decoction

2.21 mg·g-1 in the mixture and 3.58 mg·g-1 in the single herb formula combined solution in a prescription.The content of glycyrrhizic acid was 1.96 mg·g-1 in the traditional decoction

1.84 mg·g-1in the mixture and 3.04 mg·g-1 in the single herb formula combined solution in a prescription. Conclusion: The contents of licorice glucoside and glycyrrhizic acid in the single herb formula combined solution in a prescription is higher than the others. The contents of licorice glucoside and glycyrrhizic acid is significantly different in the preparation processed by different extraction methods which can provide references for Sini decoction extraction technology.