Abstract: The aim of this study is to define the main components of sapwood and heartwood as well as the differences in heartwood composition among different batches of Pterocarpus erinaceus, a kind of precious tree species. Gas chromatography-mass spectrometry (GC-MS) was adopted to analyze the main components of P. erinaceus extractives. The best extractant was selected among absolute ethanol, dichloromethane and petroleum ether. Then the main components of sapwood and heartwood from the same batch of P. erinaceus and the main components of heartwood from different batches of P. erinaceus were compared by GC-MS. Result shows that among the 3 organic solvents, dichloromethane has the best extraction ability for P. erinaceus. Based on the comparation of the total ion spectra, an obvious difference is observed between the extractum of sapwood and heartwood from the same batch of P. erinaceus, only one component is the same while other ingredients can be used as distinguishing components between sapwood and heartwood. The heartwood of 3 different batches of P. erinaceus contains 2 common components, namely 2-hydroxy-1, 2-bis(4-methoxyphenyl)-ethanone and N, N-diethyl-4-(triphenyl)-1-naphthylamine. The average relative content of 2-hydroxy-1, 2-bis(4-methoxyphenyl)-ethanone is 80.9%-82.5%, which is much higher than N, N-diethyl-4-(triphenyl)-1-naphthylamine. The most abundant component in the heartwood is 2-hydroxy-1, 2-bis(4-methoxyphenyl)-ethanone. Compare the heartwood components from 3 batches of P. erinaceus, it can be discovered that there are only 4 components belonging to a single batch, which can be taken as the characteristic components for identifying 3 batches of samples A, B and C.