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