Identifying impact factors on ecological vulnerability is essential for ecological protection. Majority of the studies have adopted the principal component analysis (PCA) and the spatial statistical method Geodetector to identify environmental factors with major impacts on ecosystem changes. However, these methods are typically limited to capturing ecological vulnerability at an annual resolution. In order to understand the long-term influences of hydrologic and environmental factors on ecological vulnerability, this study employed multivariate wavelet coherence analysis to identify environmental factors that exert long-term impacts on ecological vulnerability in the Water Conservation Region of the Yellow River Basin (WCYRB). Results indicated soil moisture (SM) has been the dominant driver of ecological vulnerability index (EVI) in the source region of WCYRB, while an integrated influence of precipitation (P), Net primary productivity of vegetation (NPP), and cultivated land proportion was more significant in the Wei-Yiluo River Basins, and increased streamflow in the WCYRB since 2010 has been primarily driven by rising P. However, the long-term impact on the ecosystem in the region has been due to large-scale atmospheric circulation patterns, with the Atlantic Multi-decadal Oscillation (AMO) associated with decadal variability and the El Nino-Southern Oscillation (ENSO)/Arctic Oscillation (AO) influencing shortterm cyclic fluctuations. This study identified areas with low and severe vulnerabilities around similar to 33 % and similar to 26 % of the WCYRB based on the multi-year average from 1990 to 2020. Future projections under the SSP2-4.5 and SSP5-8.5 scenarios indicate gradual recovery until 2050, followed by an increase in vulnerability due to climate change and water scarcity. This study provides a comprehensive understanding of their integrative impact on EVI, which provides practical implications for ecological protection and sustainable development in arid regions like the Yellow River Basin.