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In this study, we used the multi-temporal Landsat images of 1985, 2000 and 2017 to evaluate the land use/cover change of Horqin sandy land in the past 33 years by using the classification method of Support Vector Machine (SVM). The study shows that grassland, cropland, woodland, water area and sandy land changed significantly during this period. The analysis of Land cover/use in the Horqin sandy land reveals two separate specific trends between the first 16 years (1985-2000) and the subsequent 17 years (20012017). Generally, grassland and woodland decreased gradually, replaced by a significant increase in cropland area and a gradual expansion of sandy land prior to 2000. This could be related to the household responsibility system. While after 2000 the grassland increased. This could be due to the policy of returning grazing to grassland. From 1985 to 2017, however, the water area has continued to decrease.