The ecological environment of the Three-River Headwater Region is primitive and unique, and sensitive and complex to external influences. The Three-River Headwater Region is the largest nature reserve in China, and is also a nature reserve with the highest concentration of biodiversity in the world’s high-altitude areas, so the protection of ecological diversity in this region is particularly important. Ecological diversity is the material basis on which the entire humanity depends to survive and develop. It not only provides humans with basic needs such as food, energy and materials, and is also extremely important for maintaining ecological balance, regulating the climate and promoting the sustainable development of the region. Studying the topographical heterogeneity of the region is first of all a true grasp of the topography of the region, which has certain guiding significance for people's production and life. In addition, studying the impact of topographical heterogeneity on the climate of the region will help to study the formation and variation of regional climate.