Abstract: With the basis of the analysis of several event oil-gas source rocks,first the paper suggests that these rocks are characteristic of higher primary organic richness,peculiar diage-netic mechanism,and higher transforming ratio of hydrocarbon formation;secondly it approaches the difference of source rocks between distal and near origins;and thirdly it proposes that a complete system of event oil-gas source rocks can form into quite favourable oil-gas pools of lithological trapping type.Furthermore,correlative study is made on geological and geochemical characteristics of event source rocks with those ordinary ones;finally it concludes the concept,type,formative mechanism and research significance about event oil-gas source rocks.