Abstract: In order to compare chemical compositions of volatile components in the flower of Leucosceptrum canum Smith by means of different methods and different reagents, volatile components in Leucosceptrum canum Smith was extracted by using steam distillation extraction and ultrasonic extraction and the compositions of volatile components were identified by gas chromatography-mass spectroscopy (GC-MS) . The result showed that the composition and content of the volatile components have some differences with different methods and dissolvant. Four kinds of volatile compounds were identified by using steam distillation extraction, mainly was the esters, when the volatile components were extracted by ultrasonic, then could obtain 11 kinds of volatile compounds by diethyl ether extraction, 21 kinds of volatile compounds by dichloromethane extraction, 15 kinds of volatile compounds by petroleum ether extraction, mainly was the alkanes.