Terrain is an important influencing factor of land use/cover change, it is of great significance to study the relationship between land use and terrain gradient. To analyze the relationship between elevation, slope, aspect, terrain niche index (TNI), topographic relief (TR), and land use, this study took the Qinghai-Tibet Plateau (QTP) as the research area, adopted the five periods of land use data from 1980 to 2015 and Digital Elevation Model (DEM) data, using the topographic distribution index and the comprehensive index of land use degree. The results were as follows: (1) The optimal calculation window size for TR in the QTP was 31.4841 km². (2) The terrain gradient effect of grassland, built-up land, cropland, forest, and water body was significant. Unused land mainly affected the comprehensive index of land use degree. (3) The comprehensive analysis of TNI could better analyze the impact of terrain on land use. (4) The main driving factors were natural and human factors. The results revealed the terrain gradient effect of land use in the QTP, which could provide a reference for overall land planning, management, and sustainable use of land resources.