Cognomen Pengjaeng (Pengjaeng 
) , across the world, is a very rare last name. The cognomen Pengjaeng is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Pengjaeng | Thailand |
Araya, Aiyara, Chonlada, Jittranuch, and Thanaporn