Surname เพชรจำนงค์ (เพชรจำนงค์, Petjumnong 
, Pethchamnong ) , in the entire world, is a very rare cognomen. The last name เพชรจำนงค์ is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Pethchamnong, Petjamnong, Petjumnong | Thailand |
Pechjumnong, Petchamnong, Petchumnong, Phetchamnong, Phetchjumnong, Phetjamnong, and Phetjumnong