Data on the physicochemical properties and the hydrocarbon and trace-element compositions of hydrocarbon fluids from various oil and gas basins in China have been analyzed and summarized. The distribution of a wide range of hydrocarbon biomarkers in crude oils has been correlated with the salinity of lacustrine sediments. The variety of facies that characterize the burial and transformation of the original hydrocarbon-generating organic matter is reflected in particular features of oil composition. The parameters identified are recommended for geochemical correlation of crude oils with rock organic matter and for prediction of the physicochemical properties or the hydrocarbon and trace-element compositions of oil accumulations.