Cognomen อุ่นโรจน์ (อุ่นโรจน์, Ounroj 
) , throughout the world, is an extremely rare last name. The cognomen อุ่นโรจน์ is habitual in South-eastern Asia, particularly Thailand, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| Ounroj | Thailand |