Family name Lerthanakun (Lerthanakun 
) , in all the world, is a very rare cognomen. The surname Lerthanakun is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Lerthanakun | Thailand |
Sasicha, Laddawan, and Watthikorn