Abstract: As a natural environment factor, the topography affected the change of regional land use to a certain extent, and had an important impact on the spatial pattern and structural characteristics of the regional land use. By taking Langzhong City as the research object and based on the vector data and DEM data of land change survey in 2019, the spatial analysis function of ArcGIS combined with the fractal dimension and stability indexes were used to analyze the terrain gradient effect of land use in Langzhong City, so as to clarify the spatial fractal characteristics of land use in Langzhong City. The results showed that: (1) Various land use types in Langzhong City had obvious terrain gradient characteristics, and the three factors including elevation, slope and terrain niche had significant influence on the formation of the spatial distribution pattern of land use in Langzhong City; (2) The dominant distributions of cultivated land, garden land, residential land, industrial and mining land and water area were concentrated in the interval with the terrain niche index of 1, and the dominant distribution of grassland was concentrated in the interval with the terrain niche index of 6-7, while that of forest land was concentrated in the interval with the terrain niche index greater than 2. Other land use and land for transportation had no obvious concentration areas of dominant distribution. (3) The fractal dimension of various land use types in Langzhong City ranged from 1.2 452 to 1.9 855. The spatial distribution of land use types showed obvious fractal characteristics, of which the water area and land for transportation were the most stable, followed by the stability of other land, residential land, industrial and mining land, garden land and grassland, while the stability of cultivated land and forest land was relatively poor.