Abstract: Mid-Lower Jurassic coal seams are developed in eastern Tarim basin and its peripheral depressions, Triassic coal bed/line occurred in Kuqa depression and some areas of northern Tarim basin, they might be major terrestrial source rocks in Tarim basin.Specific composition and distribution are found in saturated hydrocarbon biomarkers, such as tricyclic terpanes, pantacyclic triterpanes and steranes, and aromatic compounds, showing obvious characteristics of terrestrial higher plant origin and oxidation depositional environment.Abundant alkylcyclohexans and alkybenezes in the samples indicated that bacteria are an important composition in organic matter of coal.

Key words: Tarim basin, Mesozoic, Coal bed, Biomarker, Aromatic hydrocarbon