Roing is situated in the eastern part of Arunachal Pradesh, positioned at the transition zone where the vast plains of the Brahmaputra Valley meet the steep inclines of the Eastern Himalayas. It serves as a base camp for the Mishmi Hills, which rise sharply to the north and east of the town.
The area is predominantly drained by the Dibang River, a major tributary of the Brahmaputra, and its various feeder streams like the Eze (Deopani) River, which flows right past the town. The geography is characterized by dense evergreen and semi-evergreen subtropical forests. Because of the sharp variations in altitude within a short distance, the region boasts an incredibly rich biodiversity, supporting rare orchids, diverse avian species, and elusive mammals like the hoolock gibbon and the Mishmi takin.
Natural features like Mehao Lake—a natural, oligotrophic lake nestled in the mountains—and the surrounding Mehao Wildlife Sanctuary highlight the region's pristine and untamed ecological landscape.