Climate change is one of the biggest environmental threats to mountain ecosystem. The Eastern Himalaya (EH hereafter) is rich in biodiversity due to diverse ecosystems, culture and varied micro-environment. These rich ecosystems and the biodiversity there are of global significance. The prevailing climate change trend in the Himalayas are bringing alarming signal of biodiversity lost leading to vulnerability. However, little is known about the potential impact of climate change on the fragile ecosystems of the EH both because of the paucity of past research and present priority. In this chapter, we bring forward the significance of the EH in terms of ecosystems and floral diversity and share the results from the fairly recent studies to highlight the perspective indicated.