As the residual of organic matter produced by the plant photosynthesis, the vegetation net primary productivity (NPP) forms an important part of the global carbon cycle. It is significantly affected by anthropogenic activities and climate change. The Liao River basin is located in a typical temperate monsoon belt of the northeastern part of China. Because of its ideal climatic conditions, the basin is suitable for farming and grazing. However, the increasing anthropogenic activities and global climate change have resulted in severe environmental problems within the basin. The present study within the Liao River basin focused on evaluating the impacts of climatic factors on water resources and providing practical solutions to protect these resources. By analyzing and assessing vegetation NPP in the Liao River basin, it is possible to provide a scientific basis to improve the ecological environment of the basin. Using the annual vegetation NPP data from MOD17A3 dataset from 2000 to 2015, we analyzed the spatio-temporal characteristics of vegetation NPP in the Liao River basin with methods of difference and linear trend analysis. The results showed that the increasing annual vegetation NPP ranged from 238 to 334 g/(m~2·a) carbon and was higher in the east and lower in the west. Vegetation NPP in the Liao River basin had obvious regional differences. In the Liao River tributary valley, the area with the highest NPP (348.17 g/(m~2·a) carbon) was mainly distributed in the Huntai River sub-basin, and the minimum value (217.23 g/(m~2 ·a) carbon) was distributed in the Xiliao River sub-basin. In addition, the areas with increase in vegetation NPP occupied 95.1% of the basin area. It were found by analyses of land use changes in the Liaohe River basin that area of the wetlands increased by 53.2 km~2 in 2015 compared with that in 2000, and the average vegetation NPP of the wetlands ranged from 304.8 g/(m~2·a) carbon to 367.7 g/(m~2·a) carbon. As a whole, annual precipitation and mean annual relative humidity were emerged to be dominant driving factors of vegetation NPP dynamics in Liao River basin from 2000 to 2015, but the influence factors in different tributary valleys varied.