Cognomen Kaosiriwat (Kaosiriwat 
) , in all the world, is a very rare surname. The last name Kaosiriwat is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Kaosiriwat | Thailand |
Methee, Setthawut, and Natenapang