Cognomen Phengthalangsy (Phengthalangsy 
) , across the world, is a very rare family name. The family name Phengthalangsy is habitual in Laos, where it is a rare surname, and the United States, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| Phengthalangsy | Laos, United States |
| poutavanh phengthalangsy Laotian sprinter, LA (b. 1971) |
|