Abstract: To enhance the fundamental scientific understanding of fine-grained sedimentation in saline lacustrine basins and to expedite shale oil exploration in China, this study focuses on the Eocene saline lacustrine sediments (the upper member of the Lower Ganchaigou Formation) within the Qaidam Basin, summarizing previous research insights regarding the development mechanism of high-quality source rock and the enrichment process of shale oil and discussing existing deficiencies that require urgent attention. The Qaidam Basin is a saline lacustrine basin situated within a mountainous plateau, characterized by a complex hydrocarbon-generating organism composition that includes three primary categories: algae, bacteria, and higher plants. Notably, Botryococcus braunii blooms under conditions marked by intermittent warm-humid climates and nutrient-rich diluted water column, demonstrating a clear responsive relationship with high-quality source rock development. The "relatively eutrophic," "moderate salinity," and "appropriately anoxic" environments promote elevated primary productivity alongside suitable preservation conditions that collectively enhance organic matter accumulation within the saline lacustrine basin. Saline lacustrine source rocks exhibit a characteristic "two-stage" hydrocarbon generation process; soluble organic matter generates oil during immature stages while kerogen produces oil during mature stages, thereby establishing a material foundation for shale oil enrichment from a sourcing perspective. Well-developed layered calcareous dolomite with favorable physical properties ensures large-scale shale oil accumulation from a reservoir standpoint. Diverse source-reservoir combinations dictate differential enrichment patterns of shale oil; specifically, integrated-type shale oils accumulate through self-generation and self-storage processes exhibiting high hydrocarbon contents, whereas differentiated-type shale oils rely on micro-migration for accumulation but display lower overall hydrocarbon contents despite possessing higher light component content. The sub-salt zone within the upper member of the Xiaganchaigou Formation represents an essential stratum for developing high-quality source rock and serves as a critical layer for contemporary shale oil exploration and production. However, its thickness exceeds 1,200 meters, making it a focus of research to further pinpoint the sweet spot of shale oil. The distinctive formation background of the Qaidam Basin serves as a paradigmatic case for researching the development mechanism of source rocks and the enrichment process of shale oil under extreme water body circumstances. Numerous scientific challenges necessitate comprehensive investigation, including cycling pattern of lake nutrient elements under the condition of high-salinity water medium, the differential enrichment mechanism of organic matter in diverse salinization stages, the synergistic variation patterns between biological systems and environment and their influence on the quality of source rocks, the hydrocarbon generation process and reservoir formation model within extremely thick shale sequences and their dissimilarities, as well as the occurrence and enrichment mechanisms of shale oil associated with diverse source-reservoir combinations, etc. All these are of significant importance for further clarifying the development mechanism of shale sequences in the Qaidam Basin and facilitating the increase of reserves and production of shale oil.