Abstract:The tight reservoir with high closure stress in Junggar basin refers to the ones whose depth exceeds 3 500 m and closure stress gradient higher than 0.02 MPa/m, which is characterized by poor reservoir physical properties, high Young’s modulus and Poisson's ratio, and therefore leading to high fracture pressure. The typical reservoirs in Junggar basin mainly includes the Permian reservoirs in northwestern margin of Chepaizi uplift, Jurassic and the Cretaceous reservoirs and the ones penetrated by some risk exploration wells. There are many difficulties about the reservoirs: very high wellhead pressure, easy to form complex fractures because of natural fractures, proppant bridge because of the narrow fractures, high risk because of long time and high slurry rate, and so on. This paper presents 3 technologies: wellhead pump pressure reduction technology, proppant optimization technology and parameters optimization technology. These technologies can increase the well fracturing success rate of tight reservoirs from 50% to 100%. It has provided technical supports for the tight reservoir exploration and development of Junggar basin.