Surname สิทธิอวยชัย (สิทธิอวยชัย 
) , in the world, is an extremely rare family name. The cognomen สิทธิอวยชัย is characteristic of South-eastern Asia, particularly Thailand, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| สิทธิอวยชัย | Thailand |