Abstract: Yanwu-Sancha region in Ordos basin is an oil enrichment area with multiple superimposed oil layers.However,due to low development degree and complex geological conditions,hydrocarbon exploration has not achieved bigger breakthrough in that block.Based on delta sedimentary system of Chang 8 reservoir,provenance analysis has been carried out.Through comprehensive analysis of light mineral components,clastic rock characteristics,heavy mineral characteristics and quartz cathode luminescence and granularity characteristics has been done.The results indicate controlled and affected by provenance in the southwest,the parent rocks of Yanwu-Sancha area come from the combination of metamorphic rocks and acidic magmatic rocks of ancient land in west Gansu and Qinling in the south.