Objective:To establish an UPLC-MS method for determination of Clenbuterol hydrochloride in Chinese patent medicines.Method: Ultra performance liquid chromatography tandem three quadrupole mass spectrometer was adopted

LC condition:A agela Venusil MP-C18（2.1 mm×50 mm

3 μm） column was used with the isocrstic elution of methanol and 0.2% methanoic acid at a flow rate 0.3 mL · min-1.MS condition: adopted electrospray ionization（ESI）

and multiple reaction monitoring

The relative intensities of the detected qualitative ion pairs using for qualitative

integrating the signals of the detected quantitative ion pairs using for quantitative.Result: The clenbuterol hydrochloride had good linearity with correlation coefficient>0.999 8

ranging from 1.092-27.300 μg · L-1.The average recoveries were 97.26%.The limit of quantitation was 0.19 pg.Conclusion: This method is reliable qualitative and quantitative accuracy

simple and rapid

and can be used for proprietary Chinese medicines illegally added clenbuterol hydrochloride detection.