Surname ราชธรรม (Rachatham 
, ราชธรรม , Ratchatham ) , across the world, is a very rare last name. The cognomen ราชธรรม is characteristic of Thailand, where it is a very rare surname, and Canada, where it is an extremely rare surname. Also, ราชธรรม is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Ratchatham, Rachatham, ราชธรรม | Thailand |
| Ratchadham | Thailand, Canada |