Surname สนธิวัฒน์ (สนธิวัฒน์ 
, Sontiwat , Sonthiwat 
) , around the globe, is a rare family name. The last name สนธิวัฒน์ is characteristic of South-eastern Asia, particularly Thailand, where it is a rare surname. Also, สนธิวัฒน์ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Sontiwat, Sonthayawat, สนธิวัฒน์ | Thailand |
| Sonthiwat | Thailand, United States |