Abstract: Source analysis is the most basic and important aspect in sedimentary facies research of basins. At present, there are various ways on source analysis, such as heavy minerals, clastic rock components, sporopollen analysis, sedimentary analysis, fission track, geochemistry, isotop-ic methods and so on. Based on comprehensive analysis of clastic rock components, heavy minerals and geochemistry, the sediments of the chang - 6 oil - bearing strata group of the Yanchang formation come from NE area, its parent rock is gneiss, and the background of geostructure is passive continental margin.