Quaternary salt lakes in the Qaidam Basin, northern Tibetan Plateau, host extensive sedimentary and salt mineral deposits. In this study, we conducted a detailed stratigraphic and sedimentary facies analysis of Quaternary deposits to reconstruct the basin's paleogeographic evolution. We systematically reviewed 233 Quaternary stratigraphic sections, supplemented by new data from 9 measured or revised outcrops, including age determinations and sedimentary facies observations. Four coarse-grained (gravel-dominated) lithostratigraphic units along the basin margin were revised or newly defined (the Lower-Middle Pleistocene Qigequan Formation and the Upper Pleistocene Guolemude, Holocene Nalenggele, and Holocene Xishatan formations). These refinements provided the foundation of a new temporal-spatial stratigraphic framework, enabling a detailed lithofacies and paleogeographic reconstruction of the Early Pleistocene, Middle Pleistocene, Late Pleistocene, and Holocene. Key observations include the dominance of large freshwater lakes during the Early Pleistocene, reduced subsidence and the onset of extensive salt precipitation in the Middle Pleistocene, and the intensification of mountain uplift and aridity leading to gravel deposition and brine sedimentation in the Late Pleistocene. The Holocene is characterized by hyper-arid conditions, resulting in the fragmentation of paleolakes into isolated salt lakes and dune fields, reflecting minimal freshwater recharge and pronounced evaporation. The results also clarify how tectonic uplift of the surrounding mountains and paleoclimatic fluctuations influenced the basin's stratigraphic evolution, depositional environments, and salt mineral accumulation, providing a clearer understanding of the complex dynamics that have shaped the Qaidam Basin's geological evolution.