Cognomen กุลชัย (กุลชัย 
, Kulchai 
, Kunlachai ) , in the world, is a rare family name. The last name กุลชัย is characteristic of South-eastern Asia, particularly Thailand, where it is a rare surname, and Malaysia, where it is an extremely rare surname. Likewise, กุลชัย is the forename as well as the last name.