Cognomen Rujanapun (Rujanapun 
) , in all the world, is a very rare family name. The family name Rujanapun is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Rujanapun | Thailand |
Nares, Malasri, Khemmagorn, Narathip, and Narawadee