The wood of Taxus yunnanensis (Taxaceae) showed growth inhibitory activities against human cancer cell lines, such as cervical HeLa adenocarcinoma. The morphological changes indicated that the cellular growth inhibitions were caused by apoptosis. To determine the active components, T. yunnanensis wood was analyzed by using a liquid chromatography-Fourier-transform MS (LC/FT-MS) technique. As a result, taxane-type diterpenes, such as 10-deacetylcephalomannine and 10-deacetyltaxol, were found to be present in amounts consistent with the growth inhibitory activity.