Last name รัชพันธุ์ (รัชพันธุ์ 
, Ratchaphan ) , throughout the world, is a very rare cognomen. The family name รัชพันธุ์ is habitual in South-eastern Asia, particularly Thailand, where it is a rare surname. Likewise, รัชพันธุ์ is the forename as well as the last name.