Abstract: An improved method for isolating certain clinically important taxane derivatives from the crude extract of a naturally occurring Taxus species comprising treating the extract by reverse phase liquid chromatography on an adsorbent; causing the taxane derivatives to be adsorbed on the adsorbent; and recovering the taxane derivatives from the adsorbent by elution with an elutant. The taxane derivatives thus isolated in pure form are taxol, taxol-7-xyloside, 10-deacetyitaxol, 10-deacetyltaxol-7-xyloside, cephalomannine, cephalomannine-7-xyloside, 10-deactylcephalomannine-7-xyloside, baccatin III, 10-deacetylbaccatin III, baccatin VI, and brevitaxane A.