Most members of the ginger family (Zingiberaceae), to which it belongs, are tropical, but like other species of Roscoea,[2] R. ngainoi grows in much colder mountainous regions.

[3] Like all members of the genus Roscoea, R. ngainoi grows from a short vertical rhizome, to which are attached the tuberous roots.

[4] The species resembles R. tibetica, but the leaf blades are smaller, the corolla tubes much longer, exceeding the calyx, and the labellum is differently shaped and has white lines at the base.

The specific epithet ngainoi is derived from the Ngaino peak in Manipur, where the species was first found; the type specimen was collected in March 2005 at an altitude of 2,840 m (9,320 ft).

The unusual mountainous distribution of Roscoea may have evolved relatively recently and be a response to the uplift taking place in the region in the last 50 million years or so due to the collision of the Indian and Asian tectonic plates.