Abstract: AimTo study the MS/MS fragmentation mechanism of Taxol, and based on it to establish HPLC-ESI-MS/MS technique to separate and identify Taxol in the crude extracts of ^{Taxus cuspidata} and its callus culture, consequently to provide a fast and credible method for the analysis of Taxol in natural products. MethodsOptimized the HPLC-ESI-MS/MS parameters for the sample analysis, and then discussed the ionization and cleavage mechanism of Taxol in ESI-MS and ESI-MS/MS, finally identified the Taxol in the samples with retention time, molecular weight and MS/MS spectra. ResultsElucidated the MS/MS fragmentation mechanism of Taxol, and developed HPLC-ESI-MS/MS method to analyze Taxol in the two samples.ConclusionThe HPLC-ESI-MS/MS method is rapid, highly sensitive and specific, so it is suitable for the separation and identification of Taxol in natural products.