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Paleoenvironmental changes in the Gobi Desert of Mongolia are of global significance because fluvial and lacustrine deposits in the region constitute one of the dominant sources of Northern Hemisphere dust. A series of well-preserved geomorphic shoreline features at different elevations around the Gaxun Nur basin, central Gobi Desert, indicate past fluctuations of the basin's terminal lake. We measured the exact elevation of shorelines in the basin using a Differential Global Positioning System, and found six shorelines at similar to 24, similar to 20, similar to 18, similar to 16, similar to 15m and similar to 8m above the modern basin floor. Quartz optically stimulated luminescence and K-feldspar postinfrared infrared stimulated luminescence methods were used to date these shoreline features. The reliability of the dates was confirmed using internal checks of luminescence characteristics and by comparing the quartz and Kfeldspar ages. Our results suggest a lake developed in the Gaxun Nur basin by at least similar to 121 ka. Lake levels increased from similar to 8 to similar to 24m from similar to 121 to similar to 85 ka. A 20-13-m-deep lake again formed in the basin between similar to 8.4 and 0.8 ka. Monsoonal precipitation and temperature variations during Marine Isotope Stage 5 and the mid-late Holocene were the likely causes of paleolake formation and lake level fluctuations. Copyright (C) 2017 John Wiley & Sons, Ltd.