Analysis of vegetative net primary productivity (NPP) in response to climate change has been one of the core issues of global change studies. The grassland ecosystem in Xinjiang is extremely fragile and sensitive to climate and environmental changes. Hence, it is particularly important to investigate grassland net primary productivity and its response to climate change in Xinjiang. This study simulates the NPP of Xinjiang grassland vegetation with the CASA model based on remote sensing data and measured data from field stations and describes the relationship between spatial patterns of the NPP on the Xinjiang grassland and meteorological factors from 2001 to 2014.(1) Through accuracy verification with the measured biomass data, it was shown that the CASA model can basically reflect the NPP of Xinjiang grassland vegetation.(2) The average value of the NPP of the Xinjiang grassland from 2001 to 2014 was 102.49 gC m^-2a^-1. There are significant differences in NPP among different grassland types. The NPP of mountain meadows is the highest, reaching 252.57 gC m^-2a^-1, followed by that of the temperate meadow grasslands, with 204.93 gC m^-2a^-1. The NPP of alpine desert and temperate grassland desert is the lowest, at 43.94 gC m^-2a^-1 and 53.11 gC m^-2a^-1, respectively. (3) The spatial distribution pattern of the NPP of Xinjiang grassland vegetation has the following characteristics: the NPP of the mountain grassland is higher than that of the basin grassland, and the NPP of the grassland in northern Xinjiang is higher than that of the grassland in southern Xinjiang.(4) Rainfall can promote an increase in the NPP of Xinjiang grasslands. In particular, in grasslands with less precipitation but higher temperatures, such as temperate desert grasslands, temperate grassland deserts, temperate deserts, and lowland meadows, annual precipitation and summer and autumn precipitation have a significant impact on grassland NPP. However, the temperature has little influence on the NPP of the Xinjiang grassland. By analyzing the spatial patterns of the grassland in Xinjiang, the response of grassland NPP to climate change was studied in order to provide a decision-making basis for the rational planning of grassland production and utilization, the healthy development of grassland ecosystems and the response to climate change.