Surname Sounthonnavong (Sounthonnavong 
) , worldwide, is a rare family name. The last name Sounthonnavong is habitual in South-eastern Asia, particularly Laos, where it is quite a rare surname.
| VARIANT | COUNTRY |
|---|---|
| Sounthonnavong | Laos |
Phonvilay, Phetdavanh, and Phonvilay Kat