Abstract: A portion of the powdery mahogany sample (50.0 mg) was placed into a head-space flask, and the solid phase micro-extraction was carried out with PDMS-CAR-DVB fibrous head under the following conditions:① equilibrium temperature was 60℃; ② equilibrium time was 20 min; ③ adsorption time was 15 min. The adsorbates were then desorbed at the sample inlet of the instrument at 260℃, and the GC-MS analysis was carried out under the working condition of the instrument. Non-polar DB-1MS chromatographic column and medium polar DB-17 chromatographic column were used. Two-dimensional modulator was used in the course of GC separation. The use of 2 chromatographic columns with different polarity and the modulator led to the possibility to have a better separation and higher sensitivities of giving 182 peaks with narrow peak width. Fifty-six volatile chemical components in Pterocarpus macarocarpus Kurz mahogany were found and identified by this method, accounting for about 94.3% of the total volatile chemical components. Average RSDs found were 8.5% (intraday) and 11% (interday). It is obvious that the method gives good repeatability and reprocibility. 3 mahogany samples of Pterocarpus macarocapus Kurz from various owners were analyzed by the proposed method. It was revealed by the analytical results that among the volatile chemical components, 6 compounds, i.e., α-eudesmol, β-eudesmene, eucalyptol, hinesol, eudesmin and α-elemene, were considered to be the basis of the odor of mahogany.