Surname Николаиев (Nikolaiev 
, Николаиев 
) , worldwide, is a rare cognomen. The surname Николаиев is habitual in Afghanistan, where it is a rare surname, Estonia, and Ukraine, where it is a very rare surname. Measured by absolute frequency, it is the most numerous in Afghanistan, Russia, and Ukraine.
| VARIANT | COUNTRY |
|---|---|
| Nikolaiev | Germany, Spain, United States, Afghanistan, Ukraine |
| Николаиев | Russia |