This study was carried out to examine the changes of soil physical and chemical properties and their spatial he-t erogeneity on the rainfed farmland of Horqin Sandy Land in the desertification process using methods of classical stat istics and geostatistics. Sixty soil samples of 0~10 cm layer were taken on the 300 m×90 m scale. The data were analyzed geostatist ically to determine the degree and nature of spatial heterogeneity. The results showed that soil part icle size distribution develop towards being coarse, soil waterholding capacity and porosity distribution deteriorated, and soil organic C and N, P nutrients depleted in the desertification process. The variability of soil parameters increased and the coefficient of variation ranged from 5.9% (bulk density) to 50.7% (organic carbon). Geostatistical analysis revealed that there are clearly regular changes in the pattern of distribution and high degree of spat ial variability in soil properties in the desertification of the farmland. Semivariograms and its model well reflected the degree and spatial scale of the development of desertification. In the studied area, the strip of land, where desertification developed inside the edges of the farmland along the longitudinal direction was about 100 m wide. There were close relationships between soil properties and between semivariograms of soil properties, except for pH. Desertification had very significant effect on soil organic carbon and nutrients, whereas, its effect on soil pH was relatively small.