Deori is a Sino-Tibetan language spoken by the Deori people of Assam and Arunachal Pradesh. Only one clan of the Deori tribe, the Dibongya, has retained the language, the others having shifted to Assamese, but among the Dibongya it is vigorous. It is related to the Bodo-Garo languages.
The Deori and their language are frequently called Jimochaya. The Deoris are traditionally being priests of the Sutiya and Ahom Kingdoms.
Deori is spoken in Lohit district, Arunachal Pradesh, and in Lakhimpur district, Dhemaji district, Tinsukia district, and Jorhat district of Assam.