Ayya Vaikundar (Tamil: அய்யா வைகுண்டர்) is an avatar (the incarnation of a deity) of the Lord Narayana according to Akilattirattu Ammanai the holy book of the Ayyavazhi religion, officially a Tamil Hindu branch.
According to the sacred book Akilathirattu which is comparable to the texts of Vedas, Lord Maha Vishnu, the creator and protector of the Universe, incarnated as Lord Vaikundar in Kaliyuga after ending the incarnation as Lord Krishna. The incarnation as Lord Vaikundar was the tenth in the manifestations of Lord Maha Vishnu, who was the embodiment of Lord Shiva, Lord Vishnu and Lord Brahma. While Veda agama Akilathiratt mention him as Shri Pandara, Aandavar, Shri Mayon, Shri Narayana, Lord Vishnu, Lord Thirumal, Shri Perumal, Ayya Narayana, Shri Sivanarayana and Shri Suryanarayana, the devotees reverently worship him in the names of ‘Ayya’, ‘Lord Vaikunda Swami’ and ‘Lord Narayana Swami’.