Cognomen กุลกาญจน์ (กุลกาญจน์ 
, Kulkan 
, Kunkarn ) , worldwide, is a very rare family name. The cognomen กุลกาญจน์ is characteristic of Thailand, where it is a very rare surname, Russia, and Ukraine, where it is an extremely rare surname. Not in comparison with a country's population, it is commonest in Thailand, India, and Russia. More prevalently, กุลกาญจน์ is the forename as well as the last name.