Abstract: A method for the determination of 5 taxanes including taxol,cephalomannine,baccatin Ⅲ,7-epi-taxol and 10-deacetylbaccatin Ⅲ(10-DAB)in blending liquor was developed with optimized high performance liquid chromatography tandem mass spectrometry conditions. The taxanes were concentrated by nitrogen sweeping with thermostatic waterbath at 40 ℃,purified by dichloromethane(water:dichloromethane,6:3,v:v),and separated by Thermo Hypersil Gold C₁₈ chromatographic column(100 mm×2.1 mm,3 μm). Acetonitrile and 0.1% formic acid aqueous solution were used as mobile phase,and the positive ion mode with multiple reaction monitoring(MRM)was used to detect taxanes. The results showed that the 5 taxanes exhibited good linear relationships in the range of 0~120 ng/mL with correlation coefficients(r)of more than 0.9982;the limits of detection for taxol,7-epi-taxol and baccatin Ⅲ were 4 μg/kg,and for cephalomannine and 10-deacetylbaccatin Ⅲ were 2 μg/kg,respectively. The recoveries ranged from 71.84% to 87.68% with the relative standards deviations of 1.33%~8.82%. This simple and sensitive method could determine the five kinds of taxanes in blending liquor qualitatively and quantitatively,and assist in the identification of illegal addition of Taxus chinensis in blending liquor,and provide useful technical support for the regulation of illegal addition of Taxus chinensis in blending liquor.