The Qinghai-Tibet Plateau in China is a region strongly impacted by climate change, yet its effects are unknown on the keystone endemic forest species, P. crassifolia. Understanding changes in potential distribution and habitat suitability of P. crassifolia forest with the climate change will contribute to water conservation, forest management, and ecological protection in the upper reaches of the Yellow River. A total of 129 records of species distribution data and 19 environmental variables were chosen for modeling. The MaxEnt model was used to analyze the main environmental factors affecting the potential distribution of P. crassifolia in two periods (2050s and 2070s) and four representative emission pathways (RCP2.6, RCP4.5, RCP6.0 and RCP 8.5). The main results are follows: (1) the most important environmental variables affecting distribution of P. crassifolia and percentage variance explained were: altitude (41.85%), precipitation of driest month (19.76%), slope (12.35%), annual precipitation (6.56%), precipitation of wettest month (5.73%), and precipitation of warmest quarter (5.12%), (2) habitat suitability of P. crassifolia shifted to the northwest and into high-altitude areas under climate change scenarios, but its core distribution areas were concentrated in northeastern Qinghai-Tibet Plateau, Qilian Mountains, southern Ningxia, and Helan Mountains, (3) total area of potential suitable habitat of P. crassifolia will change significantly in the future, and change of habitat area of not suitable, low, moderate, and high suitability exceed 60%.