Family name Ruttasiri (Ruttasiri 
) , all over the world, is a very rare surname. The cognomen Ruttasiri is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Ruttasiri | Thailand |
Sarawut, Somchai, Piyawan, and Kittiyanee