Abstract: The sedimentary sequences of Triassic-Jurassic systems in Tarim Basin can be grouped into 4 types of depositional facies and 12 types of depo-sitional subfacies. The possibility of sea-water overflowings in the area during Middle-Late Jurassic time is discussed in this poper. Thereafter, the prospects for oil and gas resources and the exploration guideline for Triassic-Jurassic sequences is suggested.