Abstract: The chemical constituents from the fresh flowers of Osmanthus fragrans var. thunbergii and O. fragrans var. latifolius were analyzed by GC-MS (gas chromatography-mass spectrometry) with headspace SPME (solid-phase microextraction). The optimum sampling conditions, e. g., the polarity of the fiber coating, the temperature, the method and the time of sampling in the SPME were selected. A total of 34 compounds were identified respectively in the flowers of the two species with a 65μm polydimethylsiloxane and divinylbenzene (PDMS/DVB) SPME fiber assembly. Both quantitive and qualitative differences were found among the chemical compositions of O. fragrans var. thunbergii and O. fragrans vat. latifolius. For example the proprietary component of O. fragrans vat. thunbergii was a-cyelocitral but the proprietary one of O. fragrans var. latifolius was a, a-dihydro-a-ionone. For the same compositions of O. fragrans var. thunbergii and O. fragrans var. latifolius, the difference of the contents was more than 5 times. For example, the contents of/a-Ionone and Trans-a-Ionone in O. fragrans vat. thunbergii were 1.7%and 1.44%but in O. fragrans vat. latifolius they were O. 20%and O. 26%. However the content of Linalool oxide in O. fragrans vat. latifolius was higher than that in O. fragrans var. thunbergii.