Family name Thairaj (Thairaj 
) , globally, is a very rare surname. The surname Thairaj is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname. Much less frequently, Thairaj is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Thairaj | India, Thailand |
Apichat, Sujittra, and Khwansirinat