Cognomen Lertnapa (Lertnapa 
) , globally, is an extremely rare last name. The family name Lertnapa is habitual in South-eastern Asia, particularly Thailand, where it is an extremely rare surname. Much more frequently, Lertnapa is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Lertnapa | Thailand |
Maowong, Pittapundu, Wongnibunkij, Patchaboot, Wutthitanakornkul, and Srithongsuk