Family name Phengthaisong (Phengthaisong 
) , around the world, is a very rare surname. The last name Phengthaisong is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname. Much less frequently, Phengthaisong is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Phengthaisong | Thailand |