OBJECTIVE： To establish a method for the analysis of chemical compositions in  Periploca forrestii extract， and to provide reference for further elucidating the chemical basis of the P. forrestii. METHODS： 70％ ethanol was used to prepare P. forrestii extract. UPLC-Q-TOF-MS was adopted to analyze the chemical compositions of the extract. The determination was performed on an Agilent Eclipse Plus C18 column with mobile phase consisted of 0.1％ formic acid water-0.1％ formic acid acetonitrile （gradient eludtion） at the flow rate of 0.25 mL/min. ESI source was applied to analyze the chemical composition of P. forrestii extract in negative scanning ion mode. The chemical constituents of P. forrestii extract were confirmed by the fragment ion information， related literature and standard control comparison. RESULTS： Totally 23 compounds were separated from P. forrestii extract， and 9 compounds were indentified. The peaks of 5， 8， 9， 16， 17， 18， 22 and 23 were identified as 5-O-caffeoylquinic acid， 3-O-caffeoylquinic acid， 4-O-caffeoylquinic acid， 3，4-O-dicaffeoylquinic acid， 3，5-O-dicaffeoylquinic acid， 4，5-O- dicaffeoylquinic acid， glucoperiplocymarin and periplogenin by  comparison with  standard control. The peak of 13 was deduced as （1S，3R，4R，5R）-3-{[（2E）-3-（3，4-dihydroxyphenyl）-2-propenoyl]oxy}-1，5-dihydroxy-4-{[（2E）-3-（4-hydroxy-3，5-dimethoxyphenyl）- 2-propenoyl]oxy}cyclohexanecarboxylic acid by comparison with fragment ion information and related literature. CONCLUSIONS： The established UPLC-Q-TOF-MS method can be used for the rapid， efficient and accurate analysis of the chemical constituents in P. forrestii extract.