Abstract: The present paper deals with the organic geochemical analysis and assessment of the source rocks from the lower submember of the 2nd member of the Dongying Formation (Ed^2-1) and the 3rd member of the Dongying Formation (Ed³) in the Liaozhong depression, Liaodong Bay, with the emphasis on organic matter abundance, type and maturity based on the organic geochemical parameters such as total organic carbon (TOC), hydrocarbon potential (S₁ + S₂), hydrogen index (I_H), hydrogen/carbon ratios (H/C), oxygen/carbon ratios (O/C), maximum temperatures of thermolysis (T_max) and vitrinite reflectance (Ro). The analytical results indicate that the source rocks from the lower submember of the 2nd member of the Dongying Formation (Ed^2-1) display 0 to 3 mg/g for S₁ + S₂, 0% to 1.5% for TOC, Ro < 0.5% and III to II₂ types of organic matter, indicating immature or poor source rocks. The source rocks from the 3rd member of the Dongying Formation (Ed³) display 4 to 9 mg/g for S₁ + S₂, 1% to 1.25% for TOC, Ro < 0.5 and II₁ to II₂ types of organic matter, indicating mature or better source rocks.