Abstract: In the historical period, desertification occurred in Mu Us Desert, but the stage and cause of desertification of Mu Us Desert are still controversial. The frequency accumulation curve was established by using the chronology data of aeolian sand-paleosoil deposition in Mu Us Desert, and three desertification processes can be drawn which were corresponding to 440-570, 840-960, and 1525-1890, respectively. All these periods were all characterized by low temperature, low precipitation and high frequency of dust storms. The relationship between desertification, climate change and human activities in Mu Us Desert in the past 2 000 years was discussed by combining the high-resolution climate curve and historical human activity records. The number of people and Land reclamation area in the first two desertification periods were small, so the cold and dry climate conditions had a significant impact on the desertification process. In the third period, the population increased with a high rate, the area of land reclaimed was constantly expanding. Thus, the increase of human activity intensifies the development of desertification.

Key words: Mu Us Desert, desertification, climate change, human activities