Family name พีระรัตน์ (Phirarat 
, Peerarat 
, พีระรัตน์ ) , throughout the world, is a very rare last name. The cognomen พีระรัตน์ is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname. More frequently, พีระรัตน์ is the forename as well as the last name.