Family name ธรรมวัฒน์ (ธรรมวัฒน์ 
, Thammawat 
, Tammawat ) , throughout the world, is a rare cognomen. The cognomen ธรรมวัฒน์ is characteristic of Thailand, where it is a rare surname, and Denmark. Likewise, ธรรมวัฒน์ is the forename as well as the last name.