Cognomen ปิยธรรมเดช (ปิยธรรมเดช 
) , in the entire world, is an extremely rare last name. The surname ปิยธรรมเดช is characteristic of South-eastern Asia, particularly Thailand, where it is an extremely rare surname.
| VARIANT | COUNTRY |
|---|---|
| ปิยธรรมเดช | Thailand |