Abstract:The volatile extraction with special smell from the Choushen (Codo- nopsis sp.) in Yunnan was examined by the GC/MS/DS on Finnigan-4510 type. As the result 25 compounds were identified. The methylester of hexadecanoic acid is the richost (45.75%, relatiye) in the volatile components. It is very interesting that the serial isomer and homologous series of aromatic hydrocarbon were found in the plant.