Cognomen Lertkhumsup (Lertkhumsup 
) , all around the world, is an extremely rare last name. The family name Lertkhumsup is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Lertkhumsup | Thailand |
Prawit, Karnruthai, Gunruthai, and Thanyaporn