Vegetation is a natural component of river systems and plays important hydrological, ecological and geomorphic roles. However, vegetation cover and dynamics are controlled by numerous factors operating at multiple scales, making it challenging to determine the drivers of changes over time. The Beas and Sutlej Rivers are two of the ‘water towers’ of the Himalayas that supply water and power for large populations. Previous research has shown that significant geomorphic change has occurred over that last 150 years in both rivers, with differences in the type and magnitude of change in the last few decades. The aim of this study was to quantify the spatial distribution and dynamics of riparian and in-channel vegetation in two Himalayan rivers and evaluate the local and global drivers, such as climate change, alteration of river flows, and river geomorphic adjustment. Annual changes in vegetation cover and channel width were quantified using Normalized Difference Vegetation Index (NDVI), modified Normalized Difference Water Index (mNDWI), and a multispectral supervised classification over a 30-year period, for pre- and post-monsoon seasons, using Landsat data. The results show statistically significant upward trends in NDVI across both catchments, indicating large-scale drivers of change. Relatively greater increases in NDVI in the valley bottom and the active channel zones suggest more localized processes such as recruitment and succession of vegetation and conversion to agriculture following channel narrowing. Spatial variations in vegetation dynamics helps us to better understand vegetation-geomorphology interactions in these large systems and the impacts of human activity and climate change.