Terrain is a combination of several scales of structures, with those different structures being sensitive to different landscape process and influenced by DEM (Digital Elevation Model) resolution in different ways. It is important to separate these structures to investigate their characteristics. In this research, the spatial structure of a terrain surface Loess Hilly areas in the Loess Plateau was analyzed using a 10 m resolution DEM. A geostatistical model named Independent Structures Model (ISM) was built and used to model the semi-variance of different terrain structures with different spatial frequencies. Surface of each terrain structure was mapped by kriging. The result showed that: 1). The spatial components for elevation surface could be modelled through the modelling of semi-variance. In the study area, the elevation surface could be modelled to be three components with range of 82.5 m, 655.4 m and 1974.2 m and one trend component. The third component was the most important because the sill value was larger than the other two components. 2). The three components in the model could be shown to be consistent with half width of catchments with minimum catchment area of 0.1 km(2), 1 km(2) and 10 km(2). The result of this work are relevant for research into the scaling effect of terrain parameters and the relationship between terrain and soil erosion modelling, hydrology analysis and related fields.