Abstract: Oilsand has been found in many ground structures in northern Kashi sag, which distributed mainly in Miocene Anjuan and Pakabulake Formation, secondly in Lower Cretaceous Kzlesu Formation.The axis and two limbs of anticline are favorable for oilsand distribution where have well-developed faults. The oil-bearing content of oilsand is close to rock lithology, and therefore high oil content occur mainly in fine-grained sandstone and fine-median grained sandstone. The oil source of oilsand in northern Kashi sag came from Jurassic hydrocarbon source whose reservoir-forming stage might be from Miocene to Pliocene. Early oil reservoir had been destroyed by the tectogenesis in Later Pliocene, and forming oilsand on the surface occurrence in northern Kashi sag

Key words: Tarim Basin, Kashi sag, oilsand, distribution feature