Tibetan Buddhism is the body of Buddhist religious doctrine and institutions characteristic of Tibet, Mongolia, Tuva, Bhutan, Kalmykia and certain regions of the Himalayas, including northern Nepal, and India (particularly in Arunachal Pradesh, Ladakh, Dharamsala, Lahaul and Spiti in Himachal Pradesh, and Sikkim). It is the state religion of Bhutan. It is also practiced in Mongolia and parts of Russia (Kalmykia, Buryatia, and Tuva) and Northeast China. Texts recognized as scripture and commentary are contained in the Tibetan Buddhist canon, such that Tibetan is a spiritual language of these areas.

A Tibetan diaspora has spread Tibetan Buddhism to many Western countries, where the tradition has gained popularity. Among its prominent exponents is the 14th Dalai Lama of Tibet. The number of its adherents is estimated to be between ten and twenty million.