Cognomen Агаджаньян (Агаджаньян 
, Agadzhanyan 
, Agadjanian 
) , around the world, is a rare last name. The last name Агаджаньян is habitual in Bulgaria, where it is a rare surname, Georgia, and Belarus. Measured by absolute frequency, it is commonest in Russia, the United States, and France. Much less frequently, Агаджаньян is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Агаджаньян, Agadzhanian | Russia |
| Agadzhanyan | Russia, Belarus, Bulgaria, United States, Canada |
| Agadjanian | Georgia, Belarus, United States, Canada, France |