Abstract: In this paper,the study is mainly focused on biomarkers in the marine esquences ofthe Mid-Yangtz area. At present,the determined six types of biomarkers are sterane,di-cyclosesquiterpene,tricycloditerpene,tetracyclene, horane of a pentacyclotriterpene kind and γ-waxane. By comprehensive analysis on the characters of their composition distribution and evolution of configuration,the biogenic environment of organic matter.the kerogen types and the evolution levels in the marine sequences of local area could be clearlyoutlined.This study has an important reference value for better understanding of the organic geochemical characters of the marine sequences and the further geochemical researchin the area.