Oleg Alexandrovich Maskaev (Russian: Олег Александрович Маскаев; born 2 March 1969) is a Kazakhstani-born former professional boxer of Mordvinian origin, who competed from 1995 to 2013, and held the WBC heavyweight title from 2006 to 2008.

His father is Moksha from the Zubova Polyana district of Mordovia and mother is Ukrainian from Kuban, Southern Russia.

In only his seventh professional bout, Maskaev was faced off against Oliver McCall, who had captured a world heavyweight title by knocking out Lennox Lewis only a year before.

However, he is also noted for a weak chin that was evident in his knockout losses to contenders Oliver McCall, David Tua, Kirk Johnson, Lance Whitaker, Corey Sanders and journeyman Nagy Aguilera.

His second win over Rahman was preceded by a streak of victories that helped rejuvenate Maskaev's career and earned him the "Comeback fighter of the Year" award in The Ring magazine in 2006.

In the 5th round Maskaev landed some of his best shots on his opponents chin, but to no avail: Peter was seemingly unaffected, visibly shaking Oleg.

In late 2008 he beat opponent Robert Hawkins by UD after 10 rounds and then defeated the unheralded Rich Boruff on March 14, 2009 via first-round KO, giving him mandatory contender status to the WBC Heavyweight Championship.

He fought Nagy Aguilera on December 11 in Sacramento, California at the Memorial Auditorium in a tune up fight, but was knocked out in the first round.

Maskayev was born in Taraz, Kazakhstan (then part of the USSR) to Mordvin-Ukrainian parents and was raised in Uzbekistan.