Xinghe County, Inner Mongolia, belongs to the typical region of farming-pastoral zone in northern China and is chosen as a case study area in this paper. Based on the interpretation of the Landsat-TM data (with two digital images taken in 1989 and 2000, respectively), the landscape structure was studied by analyzing patch-size, spatial pattern, and other index to show the changing feature of landscape pattern. The results showed that farmlands and grasslands were the main landscape types in plain and hilly land of the County, and different landscape types had different scales of landscape patch-size. The patch-sizes of farmland and grassland had been apparently expanded from 1989 to 2000, while those of the forestland and waters had been shrunk. The landscape pattern had an obvious trend of fragmentation due to human activities.