Abstract: Although the study of hydrocarbon migration pathways has achieved much progress in recent years,there is still lack of integrated systematic research on the configuration of hydrocarbon migration pathways and its effect on migration and accumulation of hydrocarbon.Based on the research of types of hydrocarbon migration pathways and their assemblage patterns,hydrocarbon migration direction and migration dynamics in the southwest part of the Gudao oilfield,this paper mainly deals with the migration pathways and their patterns developed in the reservoir-forming stages.It was found that the time-space configuration of fault and sand layers could qualitatively indicate the corresponding relation from source to pool; while the shape of the fault plane and seismic pumping sources determine both the dominant migration pathway and the effects of oil-source faults.Then in combination with the spatial-effect of regional unconformity we could determine the plane distribution of hydrocarbon in different strata.Finally,all the migration pathways were organized into a system so as to better understand the migration and accumulation of hydrocarbon.