Abstract: Organic matter(kerogen,asphaltine)is quickly heated in inert gas flow to a higher temperature (550-660℃). The pyrolysis products (gasifiable) are separated into monosomy compounds through capillary column of gas chromatography. Thereafter, dependingon the distributions and relative quantities of different compounds on the chromatogram, the structural characteristics of various original polymers can be infered and compared, so as to carry out geochemical study.