Abstract: Dry-hot river valleys are primarily distributed in the Jinsha, Yuanjiang, and Nujiang river basins of Southwestern China. Characterized by severe soil erosion, sparse vegetation cover, arid and hot climatic conditions, and nutrient-poor soils, these regions represent typical ecologically fragile areas in which vegetation restoration remains particularly challenging. Understanding the interactions between vegetation and environmental factors is therefore essential for developing effective restoration strategies. This review systematically synthesizes current knowledge of the mechanisms underlying interactions between vegetation restoration and environmental factors in dry-hot river valleys. Vegetation restoration can modify local environmental conditions by improving soil structure and regulating microclimates, while variations in climatic, edaphic, and topographic factors, in turn, influence plant community distribution, establishment, and development. Future research should place greater emphasis on soil-mediated processes, plant community assembly mechanisms, and the responses of vegetation to spatiotemporal variability in hydrothermal conditions. A better understanding of these multiscale vegetation–environment interactions could provide a scientific basis for improving vegetation restoration and ecological rehabilitation in dry-hot river valleys.