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Stratigraphic investigations together with climatic proxy data measurements and reliable radiocarbon dating show a history of fluctuations of dry and wet environmental conditions in the and to semi-arid zone of northern China since the late Pleistocene. Based on these data, we are able to reconstruct shifts of the desert margin in two period extremes, the last glacial maximum (21-15 ka) and the Holocene Optimum (9-5 ka). We have compared the present desert margin with that for the two extremes. The results indicate that a southward shift of the present margin of about 3 degrees in latitude might be caused by anthropogenic impact. Hence the influence of human activity must be taken into consideration for sustainable development and environment protection. Future research will be to find a two-way feedback existing between climate and anthropogenic impacts.