Abstract: In recent years, major breakthroughs have been made in the exploration of the Jurassic lacustrine shale oil in Sichuan Basin, showing great exploration potential. In order to support the further deepening exploration, the field outcrop, logging, well drilling, coring and systematic core sample experimental data are combined to analyze the geochemical characteristics, rock brittleness, pore structure and oil and gas bearing properties of shale with various lithologic combinations in the Jurassic Lianggaoshan Formation, and identify the lithologic combination types of the dominant shale. The results indicate that the lithologic combination of shale interval in Lianggaoshan Formation is classified into three categories and five types, i.e., pure shale combination, shell type shale combination, and siltstone type shale combination; Among the five types of lithologic combinations, shale is in the mature stage, but there are differences in organic matter content, type, and brittle mineral content. The shale of pure shale combination has an average TOC of greater than 1%, Type Ⅱ₁ organic matter, and brittle mineral content of higher than 52%; The organic matter characteristics of the shale of the shell type shale combination are similar to those of the pure shale combination, but the content of brittle minerals is greater than 65%; The shale of the siltstone type shale combination has an average TOC of less than 1%, Type Ⅱ₂ organic matter type, and the brittle mineral content of greater than 65%. The main reservoir space of various combinations is composed of microfractures and inorganic pores (pore diameter of 10-500 nm). The siltstone type shale combination has a larger pore throat and better pore connectivity than the pure shale combination and shell type shale combination. The free hydrocarbon content of the pure shale combination is greater than 1 mg/g, showing good oil-bearing property. OSI of the pure shale combination and the siltstone type shale combination is greater than 100 mg/g of some samples, indicating good oil movability. The comprehensive analysis shows that pure shale combination and siltstone type shale combination are favorable lithologic combination for shale oil exploration. Benefiting from the good fracability, the siltstone type shale combination is the main sweet spot for shale oil exploration in Lianggaoshan Formation.