Surname Дадаян (Дадаян 
, Dadayan 
, Dadaian 
) , worldwide, is quite a rare last name. The cognomen Дадаян is characteristic of Armenia, where it is quite a rare surname, Russia, where it is a rare surname, and Belarus. In absolute terms, it is commonest in Russia, Philippines, and the United States. Much less frequently, Дадаян is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Дадаян | Ukraine, Kyrgyzstan, Belarus, Armenia, Russia |
| Dadayan | France, Philippines, United States, Armenia, Russia |
| Dadaian | Georgia, Israel, France, Canada, United States |