Concentrations of paclitaxel and its congeners 10-deacetylpaclitaxel, cephalomannine, 10-deacetylcephalomannine, baccatin III and 10-deacetylbaccatin III in Taxus mairei were determined by HPLC. It was found that paclitaxel is abundant in roots and stem bark. The concentrations of paclitaxel and its