Abstract: The northwestern China refers to the area of the west of Helan mountain and the north of Kunlun mountain, with an area of about 200×10⁴ km² . More than 60 sedimentary basins are developed within this area, with and area of about 130×10⁴ km² . Up to now, more than 80 oil-gas fields have been discovered, of which 13 giant oil-gas fields indicate that this area is very rich in petroleum resources with 440×10⁸ t oil equivalent, but extremely low in resource transformation ratio (about 8%), showing that it has tremendous potentials for petroleum exploration and could be one of major explorative areas for replacement of resources. In view of the structural system, evolution of petroliferous basins and control factors of oil-gas distribution, this paper discusses the oil-gas distribution rules and points out the directions or targets for petroleum exploration in this area in the future.

Key words: China, northwest, petroliferous basin, structural system, petroleum distribution