This paper discusses vulnerability of freshwater resources in large and medium Nepalese river basins to environmental change based on evaluation of water resource availability and variation, resource development and use, ecological health and management capacity; and compares the situation with selected sub-basins of the Ganges and the Mekong basins in Asia. Results suggest that water resources in the medium river basins are more vulnerable than in the large basins; and Nepalese basins, in general, are more vulnerable than other selected basins in the Asian region. The vulnerability in the Nepalese basins is more related to poor management capacity followed by resources variation and the least to development pressure. The poor management capacity is mainly related to low productivity of water use and the resources stress is related mainly to variation of the resource.