It is of great significance for the sustainable development of the Inland River Basin to understand the spatio-temporal evolution characteristics and driving factors of net primary productivity (NPP) of vegetation. Based on the Carnegie-Ames-Stanford Approach (CASA) model, this paper calculated the NPP in the plateau Inland River Basin from 1984 to 2015 and verified the model accuracy, and used Theil-Sen median method, Mann-Kendall trend test and Center of gravity model to analyze the temporal and spatial variation law of NPP. Pearson correlation coefficient was used to analyze the correlation between NPP and climate factors (precipitation and temperature), and Cross wavelet method was used to analyze the driving effects of precipitation, air temperature, El Nino-Southern Oscillation (ENSO), Arctic Oscillation (AO) and sunspot on vegetation NPP. The results showed that: (1) The annual average value of NPP in the plateau Inland River Basin from 1984 to 2015 was 85.548 gC m-2 a-1 (2007)——130.344 gC m-2 a-1 (2012), and the multi-year average was 103.737 gC m-2 a-1, and the NPP increased significantly from 2007 to 2012. (2) Most areas showed a stable state, the proportion of NPP very significantly decreased, significantly decreased, not significantly decreased, not significantly increased, significantly increased and very significantly increased area was 5.2%, 3.2%, 44.2%, 37.8%, 4.3% and 5.3%, respectively. (3) The center of gravity of NPP in the plateau Inland River Basin was mainly distributed at the junction of Abaga Banner and Xilinhot City, that is the eastern part of the plateau Inland River Basin. The center of NPP gravity was more in the northeast region, accounting for 75%, which indicated that the growth rate of NPP in the northeast region was much higher than that in other region. (4) Precipitation had a greater effect on NPP, while temperature had a small effect on the NPP in the plateau Inland River Basin. Atmospheric circulation factors and sunspots were correlated with NPP of vegetation in Inland River Basin, and ENSO had the greatest influence on NPP.