Based on the carbon-14 and TL dating of the Longrao-Nanwang profile in the North China Plain, a continuous lake sediment is attributed to the Last Glacial Maximum (LGM) (20-16 ka BP) in Ningjin Lake. Our pollen and geochemical data indicate that the LGM was not a single cold and dry condition, but an oscillatory process from cool-humid through cold-humid to cold-dry climate. The Ningjin lacustrine record further shows a simultaneous global cold event. In combination with previous records we suggest that, under a global cold background during the LGM, winter monsoons became stronger while summer monsoons became weaker.