Surname Supsak (ศุภศักดิ์ 
, Supsak 
) , across the world, is a very rare family name. The cognomen Supsak is characteristic of Czechia, where it is a rare surname, Thailand, where it is a very rare surname, and the United States, where it is an extremely rare surname. Much more frequently, Supsak is the forename as well as the last name.