Cognomen อุทัยชัย (อุทัยชัย 
, Autammachai, Utaichai 
) , across the world, is a very rare surname. The surname อุทัยชัย is characteristic of South-eastern Asia, particularly Thailand, where it is a rare surname, and Malaysia, where it is a very rare surname. Much less frequently, อุทัยชัย is the forename as well as the last name.