Cognomen ยาวรรณ (ยาวรรณ 
) , in all the world, is a very rare surname. The family name ยาวรรณ is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname. Much less frequently, ยาวรรณ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| ยาวรรณ | Thailand |