In order to clarify the control of paleogeomorphology on sedimentary system in the depression basin, implement the distribution of through the superposition analysis of paleogeomorphic units and sedimentary microfacies, it is proposed that the underwater distributary channel sand body developed in the underwater ancient trench is conducive to the formation of updip pinch-out lithologic trap; The sandy clastic flow sandbody developed in the underwater paleo-platform are favorable for the formation of lenticular lithologic traps. The results show that: the hinterland of Juggar basin during Sangonghe period is a paleogeomorphic pattern of uplift and depression alternation, which has four types of paleogeomorphic units: underwater paleo low uplift, underwater paleo groove, paleo slope break and underwater paleo platform. The delta sedimentary system is developed, which has the characteristics of relatively fine grain size, relatively deep water body and far delta extension. Sandy clastic flow sandbody are developed in Modong platform, Shawan platform and Fukang platform, and underwater distributary channel sandbody are developed in the wings of Shinan low convex, Xiayan low convex, Sangequan low convex, Shidong low convex, Dinan low convex, zhengshacun low convex and Mosuowan low convex, with good reservoir and lithologic trap conditions and favorable reservoir forming conditions, which are the most favorable exploration areas in the next step.sedimentary system, and optimize exploration field in the next step, taking the second member of Jurassic Sangonghe Formation in the hinterland of Junggar Basin as an example, the paleogeomorphology is restored by using the stratum thickness method, the paleogeomorphic units are refined, and the sedimentary micro-facies are identified by core observation. On this basis, through the superposition analysis of paleogeomorphic units and sedimentary microfacies, it is proposed that the underwater distributary channel sand body developed in the underwater ancient trench is conducive to the formation of updip pinch-out lithologic trap; The sandy clastic flow sandbody developed in the underwater paleo-platform are favorable for the formation of lenticular lithologic traps. The results show that: the hinterland of Juggar basin during Sangonghe period is a paleogeomorphic pattern of uplift and depression alternation, which has four types of paleogeomorphic units: underwater paleo low uplift, underwater paleo groove, paleo slope break and underwater paleo platform. The delta sedimentary system is developed, which has the characteristics of relatively fine grain size, relatively deep water body and far delta extension. Sandy clastic flow sandbody are developed in Modong platform, Shawan platform and Fukang platform, and underwater distributary channel sandbody are developed in the wings of Shinan low convex, Xiayan low convex, Sangequan low convex, Shidong low convex, Dinan low convex, zhengshacun low convex and Mosuowan low convex, with good reservoir and lithologic trap conditions and favorable reservoir forming conditions, which are the most favorable exploration areas in the next step.