The ecological conservation and development zone of Beijing (ECDZB) was set as an ecological and water source protection barrier for Beijing in 2005. Vegetation cover can reflect the conditions of the ecological environment, and the main factors that influence vegetation cover are climate change and human activities. In this study, remote sensing and meteorological data from 2001-2015 were used to analyze the spatiotemporal changes in vegetation cover in the ECDZB as well as their correlations with precipitation and temperature. Moreover, the relative contributions of climate change and human activities were quantitatively evaluated via residual analyses. The results showed that the annual maximum value of the Normalized Difference Vegetation Index (NDVI) in the ECDZB increased in general. Furthermore, the annual maximum NDVI was positively correlated with the annual precipitation and negatively correlated with the mean annual temperature. Moreover, the relative contribution rate of human activities to NDVI changes was 59.66%, which was higher than the 40.34% attribution of climate change. These results indicated that human activities dominated the process of vegetation cover change in the ECDZB, and the establishment of the ECDZB has played a crucial role in improving the regional ecological environment.