Surname Paiyarach (Paiyarach 
) , throughout the world, is a very rare last name. The family name Paiyarach is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Paiyarach | Thailand |
Darunee, Mongkotrat, Panisara, and Ratchaneepron