Exploring the impact of climate change on the potentially spatial distribution of forest plants in Tianshan Mountain and its simulation and prediction can help to reveal the adaptation strategies and feedback mechanisms of plant distribution patterns to climate change at the mesoscale. It has important scientific and practical significance for promoting biodiversity conservation and sustainable management of forest resources in Arid Mountainous Forest Ecosystem. Based on the data of distribution points of Picea schrenkiana and environmental factors data, the maximum entropy (MaxEnt) model, GIS tools and R software were used to estimate the potential distribution range, spatial pattern changes and niche differentiation of P. schrenkiana under the reference climatic (1970-2000), Representative Concentration Pathways (RCPs) based climate scenarios in 2050 (2041-2060) and 2070 (2061-2080). The results showed that:(1) the potential distribution of P. schrenkiana in the reference climatic was basically consistent with the Normalized Difference Vegetation Index (NDVI) vegetation cover change in autumn of 2019. The high suitability distribution areas are mainly distributed in Hami, Balikun and Yiwu in Eastern Xinjiang, the north slope of Tianshan Mountain, Bogda Mountain, Beita Mountain and Yili Valley in Northern Xinjiang, and the south slope of Tianshan Mountain in Southern Xinjiang. In addition, it was also distributed in the southern slope of Altay Mountain, Tacheng, Yumin, Tuoli, Western Kunlun Mountain and little Pamirs mountain. (2) The key factors limiting the potential distribution of P. schrenkiana were precipitation (Precipitation of driest month, Precipitation of coldest quarter and Precipitation seasonality), temperature (Mean temperature of driest quarter, Annual mean temperature, Isothermality and Annual temperature range), soil profile available water capacity, soil carbon density, and altitude. Their cumulative contribution rate reached 87.28%. (3) In 2050 and 2070 periods, the suitable distribution range of P. schrenkiana showed no significant increasing trend, but the RCP6.0 scenario was more significant than the RCP2.6, with an increase of 3.33% and 3.47%, respectively; The low, middle and high suitable areas maintained relatively stable changes, the growth rates from RCP2.6 to RCP6.0 scenarios are about 1.78%, 1.26%, and 0.98%, respectively; and the center of gravity of suitable distribution areas showed a trend towards higher latitude and northeastward, but the change amplitude was not significant. (4) PCA analysis showed that the climate niche of P. schrenkiana was the most extensive in Southern Xinjiang, followed by Northern Xinjiang, and the narrowest in Eastern Xinjiang. Niche differentiation test indicated that there was no significant differentiation in the Northern, Southern and Eastern Xinjiang.