The Udi language, spoken by the Udi people, is a member of the Lezgic branch of the Northeast Caucasian language family. It is believed an earlier form of it was the main language of Caucasian Albania, which stretched from south Dagestan to current day Azerbaijan. The Old Udi language is also called the Caucasian Albanian language and possibly corresponds to the "Gargarian" language identified by medieval Armenian historians. Modern Udi is known simply as Udi.

Udis are a native people of the Caucasus that currently live mainly in Russia and Azerbaijan, with smaller populations in Georgia, Armenia, Kazakhstan, Ukraine, and other countries. Their total number is about 10,000 people. They speak the Udi language, which belongs to the Northeast Caucasian language family. Some also speak Azerbaijani, Russian, Georgian, or Armenian, depending on where they reside. Their religion is Christianity.