The Idu Mishmi language is a small language spoken by the Mishmi people in Dibang Valley district, Lower Dibang Valley district, Lohit district, East Siang district, Upper Siang district of the Indian state of Arunachal Pradesh and in Zayü County of the Tibet Autonomous Region, China. There were 8569 speakers in India in 1981 and 7000 speakers in China in 1994. It is considered an endangered language.

The Mishmi people are an ethnic group of Tibet and Arunachal Pradesh, India. The area is known as the Mishmi Hills. Only one group, called the Deng, occupy Zayu County in southern Tibet.