Cognomen Iaroslavtsev (Ярославцев 
, Iaroslavtsev 
) , in the world, is quite a common surname. The cognomen Iaroslavtsev is habitual in Russia, where it is quite a rare surname, Kazakhstan, and Belarus. Measured by absolute frequency, it is commonest in Russia, Ukraine, and Kazakhstan.
| VARIANT | COUNTRY |
|---|---|
| Ярославцев | Kazakhstan, Belarus, Kyrgyzstan, Russia, Ukraine |
| Iaroslavtsev | Canada, United States, Russia, India |