Last name ไสยสิทธิ์ (Saiyasith 
, ไสยสิทธิ์ 
) , in the world, is a rare cognomen. The family name ไสยสิทธิ์ is habitual in Laos, where it is quite a rare surname, Thailand, where it is a rare surname, and the United States, where it is an extremely rare surname. Much less frequently, ไสยสิทธิ์ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Saiyasith | United States, France, Laos |
| ไสยสิทธิ์ | Thailand |