Family name Zadornov (Задорнов 
, Zadornov 
) , worldwide, is a rare cognomen. The surname Zadornov is habitual in Russia, where it is a rare surname, Kazakhstan, where it is a very rare surname, and Ukraine.
| VARIANT | COUNTRY |
|---|---|
| Задорнов | Kazakhstan, Russia, Ukraine |
| Zadornov | Russia, United States |