Abstract: A brief commentary has been made on advance in organic geochemistry of petroleum,including discussion of nature and oil-generating mechanism of kerogen,evolution of petroleum and primary migration.In terms of geological conditions of China,some problems in research of organic geochemistry of petroleum have been discussed,Terrestrial source rock is one of the most important types in China,so it is of great significance to investigate the texture and nature of this type of kerogen.Carbonate source rock is one essential problem we have faced in exploration of oil and gas in carbonate formations.It has been sugested that in evaluation of carbonate source rock,the evaluating indicator of organic carbon must be reduced and the study of sedimentary facies and diagenetic facies must be stressed.Some more work should be done on organic evolution characteristics and oil-forming mechanism in carbonate rock.While making perspective evaluation work in pre-Tertiary or Tertiary formation distributed area,one problem which should be considered separately is the lower limit and upper limit of petroleum evolution.In correlation of oil and oil as well as correlation of oil and source rock,more work should be done on new organic geochemical markers and new correlation principles.