Abstract: Whole rock analysis and kerogen analysis are two analytical methods of studying hydrocarbon source rock in organic petrology. Basing on the brief introduction of the two methods, the authors systematicallly compare their applications in oil and gas assessment.We think that whole rock analysis provides more information than kerogen analysis in the study of the characteristics, origin and classification of macerals, the abundance, type,
and maturity of organic matter, and the features of oil generation and migration. besides,whole rock analysis is faster, more economical and more perceivable than kerogen analysis, and so the former has obvious advantages. Though it has not completely replaced kerogen analysis so far, it is sure to be one of the methods necessary for the study of oarganic petrology in the future.

Key words: Oil &, gas assessment, Organic petrology, Whole rock analysis, Kerogenanalysis