Cognomen Исайев (Isayev 
, Исайев 
, Isajev 
) , around the world, is a common surname. The cognomen Исайев is characteristic of Azerbaijan, where it is a common surname, Bulgaria, where it is quite a rare surname, and Israel. In absolute terms, it is commonest in Azerbaijan, Uzbekistan, and Israel.
| VARIANT | COUNTRY |
|---|---|
| Isayev | Azerbaijan, Bulgaria, Israel, United States, Uzbekistan |
| Исайев | Bulgaria, Russia |
| Isajev | Czechia, Azerbaijan, Estonia, Lithuania, United States |