The Qinghai-Tibet Plateau ecological barrier area is an important part of China's ecological security strategic pattern and plays an important role in protecting the ecological security of China and even Asia. It is of great significance to study the spatiotemporal dynamics of the ecosystem and explore the driving forces that affect change in the ecosystem in the Qinghai-Tibet Plateau ecological barrier area. Based on multi-source remote sensing data, this paper analyzed the change in the ecosystem in the Qinghai-Tibet Plateau ecological barrier area from 2000 to 2015. We selected the natural and social economic factors as the driving factors, and the change mechanism of the ecological system in the Qinghai-Tibet Plateau ecological barrier area was analyzed by redundancy analysis and other methods. The results showed the following:(1) The ecological pattern of the Qinghai-Tibet Plateau ecological barrier area changed significantly between 2000 and 2015. The grassland ecosystem was reduced by 1792 km², which was mainly transformed into desert ecosystem and river ecosystem, with 1088 km² and 832 km² converted, respectively. The river ecosystem increased by 1600 km², which was mainly converted from desert ecosystem and grassland ecosystem, with 1152 km² and 832 km² converted respectively. (2) From 2000 to 2015, the socio-economic factors were the main driving mechanism for the evolution of ecosystem pattern on the Qinghai-Tibet Plateau ecological barrier area. The redundancy analysis results showed that Gross domestic product(GDP) (83%) and Population(POP) (72%) contributed the most. In the results of analysis of variance, the joint contribution rate of GDP and POP reached 77%. The results of geographical weighted regression showed that the proportion of the area dominated by socio-economic factors was 60.41%. (3) The contribution rate of POP in the Qinghai-Tibet Plateau ecological barrier area reached 72%, the area of the positive transformed ecosystem reached 86.24% under the effect of POP. Moreover, POP was highly correlated with the river and forest ecosystems. All of these showed that the implementation of the ecological protection policy and the construction of ecological projects in the Qinghai-Tibet Plateau ecological barrier area have been effective.