Family name ศิริวงศ์วรรธก (ศิริวงศ์วรรธก 
) , in all the world, is an extremely rare surname. The surname ศิริวงศ์วรรธก is characteristic of South-eastern Asia, particularly Thailand, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| ศิริวงศ์วรรธก | Thailand |