Assessing the impacts of climate change on geographic distribution by identifying how biological response relates to environmental conditions is important for addressing the adverse effects of climate change. Using the maximum entropy algorithm and spatial analysis module of ArcGIS, we construct a habitat prediction model for the geographic distribution of alpine vegetation in the Hengduan Mountains of southwestern China. We use the model to identify how alpine vegetation has responded to climatic changes during the period 1980–2018, and to predict responses to possible temperature and precipitation changes in the future. The results indicate that the geographic distribution of alpine vegetation in the Hengduan Mountains is most sensitive to annual mean minimum temperature variation. The most suitable habitat for alpine vegetation under climate change is in northernmost Sichuan, in the Hengduan–Himalayan mountain area, at elevations from 4500 to 5000 masl. The current area of alpine vegetation in the Hengduan Mountains accounts for 8.20% of their total area. As the annual mean temperature increases, the area suitable for alpine vegetation increases by 0.32–1.27%, regardless of changes in precipitation. When the temperature increases by 1–2°C, the area unsuitable for alpine vegetation decreases by 1.64–2.97%. These results indicate that a temperature increase influences the geographic distribution pattern of alpine vegetation in the Hengduan Mountains. The most notable effect was under the 2°C increase scenario. The predictions suggest that under future climate change, the geographic distribution of alpine vegetation will continue to shift toward middle and higher elevations. To protect endemic alpine vegetation, the best habitats should be protected from interference and destruction by human activities.