To resovle the problems of in-situ conservation and resource utilization of Pyrus calleryana, maximum entropy model ( MaxEnt) and geographic information system ( GIS) were used to predict the global ecological suitable region of P. calleryana in different climate scenarios based on 236 distribution data and 19 ecological factors. The results showed that the ecological suitable regions of P. calleryana were mainly concentrated in North America,Asia and other regions,with a total area of 1.6*10~7 km~2. In China,the regions with high ecological suitability were Hunan,Hubei, Anhui,Jiangxi,Jiangsu,Zhejiang and Fujian provinces. The main factors affecting the geographical distribution of P. calleryana were mean annual temperature and mean annual precipitation,followed by the seasonality of temperature. The model simulations indicated that P. calleryana would have different suitable habitat areas and marginally suitable habitat areas in different climate scenarios. In terms of the spatial distribution of the potential habitat area,both the distributional range and the center of distribution of suitable and marginally suitable habitat area would shift from east to west. The suitable habitat area in North America and marginally suitable habitat areas in Europe would increase rapidly.