Abstract: OBJECTIVE To identify the terpenoids of Kansui stir-baked with vinegar by UHPLC-Q-TOF-MS/MS. METHODS Chromatographic separation was performed on an ACQUITY UPLC C₁₈ column (100 mm×2.1 mm， 1.7 μm) with a gradient solvent system composed of 0.1% aqueous formic acid (A) and acetonitrile (B) at a flow rate of 0.4 mL/min， and the temperature of column was 40 ℃ with injection volume of 4 μL. The samples were analyzed with an electrospray ionization (ESI) interface set in both positive and negative ionization modes. RESULTS The terpenoids of Kansui stir-baked with vinegar were analyzed by Peak View SoftwareTM， 32 terpenoids were identified， including 15 ingenane diterpenes， 12 jatrophane diterpenes and 5 triterpenes. And the fragmentation of ingenane diterpenes and jatrophane diterpenes was analyzed. CONCLUSION This method is rapid and accurate， which can be applied for explaining the material basis and finding the possible mechanism of "toxicity-efficacy" of kansui stir-baked with vinegar.