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Climate change has largely affected natural ecosystems around the world, especially in arid and semi-arid regions. Rangelands have great significance in carbon cycle due to their contribution for a large part of regional net primary production (NPP). These ecosystems are vulnerable to climate change. Given the Isfahan Province, central Iran, as the study area, an attempt is made to simulate changes in the rangeland aboveground net primary production (ANPP) under three RCP (representative concentration pathways) climate change scenarios (RCP2.6, RCP4.5 and RCP8.5) for two periods (2050s and 2070s). The rangeland ANPP was estimated using a support vector machine (SVM) model with RMSE of 23.78g C m(-2) year(-1) and R-2 of 0.92. Changes in the mean annual precipitation and temperature due to climate change were projected by ensembling 14 General Circulation Models (GCMs) through a weighting approach. The results indicated trends towards drier and warmer conditions in future periods. The maximum decreasing precipitation and increasing temperature are projected to occur in western and eastern parts of the province, respectively. The mean annual ANPP showed different trends between bioclimatic zones. It decreased about 25.9% in the sub-humid and cold zone and increased over 120% in the hyper-arid and warm zone by 2070s. Generally, rangelands in western and southwestern parts of the province are found to be more vulnerable to future drying-warming condition. These results highlight the need of adopting proper policies to encounter various effects of climate change in this region.