Abstract: A large number of fatty acids in the light hydrocarbons and aromatic fractions of the extracts from thermally simulated samples of modern pine pollens were identified by GC-MS analysis. These biomarkers are clearly even carbon predominated. The major components of light hydrocarbons are palmitic(C16)，stearic(C18)，methyl esters(Cl6，C18)and ethyl esters(C16，Cl8). Aromatic hydrocarbons are relatively complex，consisting of saturated fatty acids，unsaturated fatty acids and fatty acid internal esters．The carbon number of the light hydrocarbons is from C15 to C30，and the relative distribution of C16，C18 acids(esters)is of absolute predominance. The carbon number of aromatic hydrocarbons is from C20 to C30，and the main components are C26，C28 and C30. Lower abundance of Cl8 unsaturated fatty acid was identifed at low temperature stage(<250℃ ) The expulsion of fatty acids(esters)occurred at very low temperature stages. There are two expulsion peak stages from 200℃ to 300℃ and from 300℃ to 400℃. The controlling factor is probably due to difference in hermal stabilization of different fatty acids. The free state fatty acids(esters)in the cytoplasm of pine pollens and the unsaturated fatty acid are easily banished at low temperature stage. Saturated fatty acids and the fatty acids in the lipoid of the wall of pollens would be degraded at the higher temperature stage. Original pollens and the simulated samples at low tempe rature stage mainly contain fatty esters． Simulated samples at 250℃ and higher temperatures contain more fatty acids due to hydrolysis．Fatty acids(esters)can be easily decarboxylated to produce chain hydrocarbons as the simulation temperature continuously rises. The contents of fatty acids(esters)remarkably drop down because of strong pyrolysis at the higher temperature stage over 400℃. This is consistent with the appearance of large quantity of odd carbon n-alkanes in light hydrocarbons and saturated hydrocarbons at 350～ 450℃ stage. The studies indicate that plant pollens are one of the important origins of Cl6，C18 saturated and unsaturated fatty acids(esters)in sedimentary organic of mattters．