Surname ธรรมารัตน์ (ธรรมารัตน์ 
) , all over the world, is a very rare family name. The surname ธรรมารัตน์ is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname. Much less frequently, ธรรมารัตน์ is the forename as well as the last name.