Abstract: The discovery of light oil reservoir of Neogene Shawan Formation is a great breakthrough in petroleum exploration history of the Chepaizi Uplift,the Junggar Basin.Studies of geochemical parameters such as stable isotope and biological markers have indicated that the crude oils in the region come from Jurassic hydrocarbon source rocks.Geochemical features of the Dushanzi crude oil are compared with histories of hydrocarbon generation and migration of the Jurassic source rock and tectonic evolution of the Chepaizi Uplift,proving that the light oils mainly come from the Sikeshu Sag and the faulted fold zones of the Northern Tianshan Mountain.The crude oils which sourced from Jurassic migrate vertically through deep fractures into the Neogene Shawan Formation,and then move northward or northwestward along the southern slope of Chepaizi Uplift to the Chepaizi region,and finally accumulate in proper traps.