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