Family name Niwatmethakun (Niwatmethakun 
) , all over the world, is a very rare surname. The cognomen Niwatmethakun is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname.
| VARIANT | COUNTRY |
|---|---|
| Niwatmethakun | Thailand |
Sayan, and Phitchayaporn