Climate change is one of the key factors affecting species distribution. In order to understand the ecological suitability of alpine plant in taxa Northwest China and their responses to future climate scenarios, the suitable distribution of Sorbus tianschanica and its possible response to future climate change were studied. In this study, 51 natural distribution sites and 10 environmental factors of Sorbus tianschanica were used to integrate GIS spatial analysis and MAXENT model to analyze the suitable distribution area and spatial characteristics of Sorbus tianschanica in Northwest China under baseline climate (1970-2000) and future climate (2050 period, based on RCP 4.5 scenario). Based on the multivariate environmental similarity surface and the least similar variables, the future climate fluctuations in the study area compared with the baseline climate were analyzed. The key environmental factors affecting the distribution of Sorbus tianschanica were identified by integrating the contribution value of environmental variables, the replacement importance value and the knife cutting method. GIS tools and R software ggplot2 package were integrated to analyze the numerical range of the changes of key factors in the suitable distribution area of Sorbus tianschanica in the future climate. The results show that: (1) under the baseline climate, the suitable area of Sorbus tianschanica accounts for 13% of the total area of the study area, which is concentrated in the western part of Altay, the western part of Junggar, the middle and western part of Tianshan, Bogda Mountain, Qilian Mountain, South Mountain of Qinghai, and parts of Pamir Plateau and north part of Karakoram Mountain; (2) The accuracy of the model simulation is significantly improved by adding the Normalized Vegetation Index. The distribution of Sorbus tianschanica is mainly limited by the driest monthly precipitation, the wettest monthly precipitation, and the daily range of average temperature. Regarding the suitable distribution range, the driest monthly precipitation is 0-18 mm, the wettest monthly precipitation is 6-127 mm, and the daily range of average temperature is 8.2-16.3 ℃; (3) Compared with the baseline climate, influenced by precipitation factors in 2050, the suitable distribution of Sorbus tianschanica in Altai Mountain, western Junggar Mountain, Tianshan Mountain, and Qilian Mountain will expand slightly, and the center of mass of suitable distribution area will move northward. The results of the study show that the suitable habitat area of Sorbus mandshurica in Northwest China is small and fragmented. In the future climate scenario, only the local suitable mountains will be fragmented and expanded. The predicted suitable distribution area of Sorbus tianschanica and its suitable altitude range only account for 4% of the study area. However, there is no nature reserve for this plant. It is suggested that the western part of Altay, the western part of Junggar, the western part of Tianshan Mountain and the middle part of Qilian Mountain should be taken as the risk protection areas of Sorbus tianschanica, and the eastern part of Hexi Corridor and the southern mountain of Qinghai should be taken as the high risk protection areas. The suitable and most suitable distribution area of the plant predicted in this study is helpful to guide the protection of the Sorbus tianschanica.