Tayy is an Arabian tribe belonging to the southern or Qahtanite branch of Arab tribes.

Their original homeland was the area of the two mountains Aja and Salma in north central Arabia (currently Ha'il Province, Saudi Arabia), though, like all Qahtanite tribes, it is believed they originally moved there from Yemen.

The tribe shared the area with Bani Assad and Bani Tamim, and its members included both nomads and settled town-dwellers.The tribe is believed to have included a number of Christians before Islam, though most of the tribe's members are reported to have been paganThough sections of Tayy began migrating to neighboring regions such as Iraq and Syria before Islam, Tayy participated heavily in the Muslim Conquests of the early centuries of Islam, with sections or individual members of the tribe settling in many parts of the Islamic Empire, including Lebanon and Egypt.

Most of these, however, were later assimilated into the general populations of these areas or into other tribes.