Cognomen Atthajanyakul (Atthajanyakul 
) , throughout the world, is an extremely rare family name. The last name Atthajanyakul is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Atthajanyakul | Thailand |
Panarat, Punchida, Kittichai, and Papatchaya