Family name Natthai (Natthai 
) , in all the world, is a very rare cognomen. The family name Natthai is habitual in Thailand, where it is a very rare surname, the United States, where it is an extremely rare surname, and India. More frequently, Natthai is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Natthai | India, United States, Thailand |