Cognomen ฤทธิ์ไทย (ฤทธิ์ไทย 
) , in the world, is an extremely rare last name. The last name ฤทธิ์ไทย is habitual in South-eastern Asia, particularly Thailand, where it is an extremely rare surname. Likewise, ฤทธิ์ไทย is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| ฤทธิ์ไทย | Thailand |