Abstract: Junggar basin, located at the northern part of Xinjiang, covers an area of 13 × 10⁴ km². To date, more than 30 oil and gas fields have been discovered. Many years'research shows that the basin has a pre-South China System crystallized metamorphosed basement. Under the control of Latitudinal and Xiyu systems and NE-trending structural system, Paleozoic sediment widely developed. They are characterized by deep rifting during South China and shallow and deep sea marine deposition of cratonic basin during Ordovician, deep sea deposition of compressed craton basin during Silurian and Devonian, shallow-terrestrial facies sedimentation of intracraton rifting basin during Carboniferous and Permian.