Objective: To analyze the chemical components of Glycyrrhizae Radix et Rhizoma in Pinelliae Rhizoma Praeparatum (PRP) by using ultra performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF-MS/MS). Method: The aqueous extracts of PRP were separated on Waters Acquity BEH C18 column (2.1 mm×100 mm

1.7 μm) with acetonitrile-0.1% formic acid solution as mobile phase for gradient elution. The flow rate was 0.25 mL·min-1 and the column temperature was 35℃. Mass spectrometric data were obtained under electrospray ionization (ESI) negative mode and the constituents were identified according to the exact relative molecular weight and fragment ions reported in the references. Result: Fifteen constituents were identified from Glycyrrhizae Radix et Rhizoma in PRP

including 6 triterpenoid saponins and 9 flavonoids. Conclusion: Systematic research of the fifteen chemical constituents of Glycyrrhizae Radix et Rhizoma in PRP was performed firstly in this study

which could provide the basis for clarifying the pharmacodynamic material basis and rational clinical application of PRP.