We analyzed the changes of net primary productivity (NPP) and net ecosystem productivity (NEP) of Quercus spp. forest and Robinia pseudoacacia plantation under different future climate scenarios in Shaanxi Province during 2015-2100, using the process-based dynamic vegetation model-LPJ-GUESS. The results showed that compared with the benchmark period (1961-1990), NPP of Quercus spp. forest and R. pseudoacacia plantation in northern Shaanxi would decrease by 4.9%-29.5% and 22.5%-56.2% respectively, while that in Guanzhong and southern Shaanxi would increase by 13.0%-49.0% and 21.3%-62.9% respectively in the future. The NPP of Quercus spp. forest and R. pseudoacacia plantation under the RCP scenario was the highest, followed by that under the RCP and RCP scenarios. Those two types of forest would be carbon sink in three subregions in the future. Quercus spp. forest would have stronger carbon sink function in nor-thern Shaanxi and Guanzhong, while R. pseudoacacia plantation would have stronger carbon sink function in Southern Shaanxi. Under different RCP scenarios, the NEP variation range of R. pseu-doacacia plantation was greater than that of Quercus spp. forest in three subregions.