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Detailed records of climate change during the Last Glaciation in arid central Asia are scarce. Here we present a sedimentological and geochemical record from Wulungu Lake in north-western China, providing the first high-resolution, continuous sedimentary records in this region covering Marine Isotope Stage (MIS) 3 (51 600-25 300 cal a BP). High lake power (end-member 2 values) and bioproductivity concurrent with low terrigenous clastic input unanimously indicate high lake water levels during 46 180-39 770, 31 680-30 080 and 27 780-26 540 cal a BP, and moderately wet conditions during 51 600-46 180 and 39 770-31 680 cal a BP. The lake attained its lowest water levels after 30 080 cal a BP. Few dry events characterized by high pool power (end-member 3 values) and terrigenous input are documented for the studied interval and three of them are correlative with Heinrich events 5-3. Our study supports the hypothesis for a positive Northern Hemisphere July insolation anomaly which increased the temperature gradient between low and high latitudes, increasing the strength of Westerlies and increasing sea surface temperatures in the North Atlantic, resulting in more moisture transported to arid central Asian by Westerlies.