1. Shenyang Center of Geological Survey, CGS, Shenyang 110034, China;
2. School of Earth Environment and Water Resource, Yangtze University, Wuhan 430100, China;
3. Liaohe Oilfield Company, PetroChina, Panjin 124010, Liaoning, China

Based on the core, measured geological profiles, and testing data, the depositional environment and the organic geochemical characteristics of source rocks in the Beipiao Formation of the Jinyang Basin were analyzed. The results show that Beipiao Formation was deposited in freshwater-brackish water environment with partial oxidation,and the climatic changed from humid,semi-humid to semi-dry orderly. The sources rocks are in high abundance of organic matter, which mainly consists of type ��₂ and some type �� organic matter. The source rocks are mature and are at the peak of oil generation. Laterally, sources rocks at the Dongkuntouyingzi geological profile and the Shimengou geological profile located in the depositional center of Zhangjiyingzi depression are with high organic matter abundance, and are defined as medium-good source rocks. The source rocks at Diaojiagou geological profile located at the marginal facies of deposition are the worst in terms of organic matter abundance, and are defined as non-poor source rocks. In vertical aspects, the semi-deep lake facies is better than shore-shallow lake facies in terms of organic matter abundance. Braided river delta and fan dalta facies are with non-poor source rocks.