Last name พูนสิทธิ์ (พูนสิทธิ์ 
, Poonsit 
, Phunsit ) , all over the world, is a rare cognomen. The surname พูนสิทธิ์ is habitual in South-eastern Asia, particularly Thailand, where it is a rare surname. Likewise, พูนสิทธิ์ is the forename as well as the last name.