Family name พลอยศิริ (พลอยศิริ 
, Ploysiri 
, Phloisiri ) , throughout the world, is a very rare cognomen. The surname พลอยศิริ is habitual in South-eastern Asia, particularly Thailand, where it is a rare surname. More frequently, พลอยศิริ is the forename as well as the last name.