There is a great difference in the gross composition and biomarker distribution between chloroform extracts of coal and oil from coal measures, which results in a difficulty in oil-source correlation in a coal-bearing petrolific basin. An experiment extracting 9 coal-bearing source rocks and 3 lacustrine source rocks with four different polarity solvents , hexane, benzene, dichloroformethane,chloroform,shows that, with the increase of polarity of solvents, the content of extracts increases, and the relative content of saturated hydrocarbon in the extracts decreases. The chemical composition of the hexane extracts is the most similar to that of oils from coalmeasure basins in the four kinds of solvent extracts. Although there are great differences in content and chemical composition among the four extracts, the distribution pattern of normal hydrocarbons and isoprenoids have little changes. A comparison indicates that the absolute concentration of biomarkers of sterane and terpane in the hexane extracts is relatively lower than that in the chloroform extracts, and the difference of biomarker concentration between the two extracts of coal-bearing source rocks is greater than that between the two extracts of lacustrine source rocks, but the components and distribution characteristics of biomarkers in the two extracts of a source rock are essentially similar within the polarity range of ordinarily used solvents. Based on the statistics of 18 kinds of biomarker in each extracts from 10 source rocks containing different content of organic matter, the percentage exceeds 84%,whose relative error of a compound between hexane extracts and chloroform extracts (including analytical error) is less than 5%, and the percentage is less than 5%, whose relative error is greater than 10%. This result indicates that polarity of solvents controls the relative content of saturated hydrocarbon and absolute concentration of biomarkers in coal extracts, but cannot change component and distribution pattern of biomarkers in coal extracts. So, the difference in gross composition and content of saturated hydrocarbon between hexane extracts and chloroform extracts does not influence the application of biomarkers to correlating oil and source. The biomarkers in extracts obtained by chloroform as an ordinarily used solvent to extract organic-rich source rocks, such as coal and carbonaceous shale, can be applied to the oil-source correlation in coal-bearing petrolific basins.