His professional MMA debut came in April 2009 when he defeated Nikolay Pleshakov by TKO in just 80 seconds.

[6] In December 2009, after just eight months as a professional fighter,[6] Volkov faced Ibragim Magomedov at M-1 Challenge 20 - 2009 Finals.

Coming in as an underdog, his team simply wanted him to make it through all three rounds, but Volkov exceeded expectations by winning via unanimous decision.

[7] Volkov faced Denis Smoldarev on February 19, 2016, M-1 Challenge 64 for the vacant M-1 Global Heavyweight title, he won the fight via submission (triangle choke).

Volkov faced former Bellator light heavyweight champion Attila Végh on June 16, 2016, at M-1 Challenge 68.

Within his first year of professional competition, Volkov was competing in the M-1 Eastern European tournament,[7] taking victories in the opening round and the semi-final.

To reach the championship fight, Volkov first had to take on Maxim Grishin to become the Eastern Europe champion.

Unfortunately for Volkov, he fell prey to a rear-naked choke early in the opening round and was eliminated.

His opponent was the debuting Eldar Yagudin, who he defeated inside the opening round by TKO (punches).

[10] In his first title defense, Volkov faced Vitaly Minakov in the co-main event at Bellator 108 on November 15, 2013.

[16] Nearly a year since his last fight for the promotion, Volkov faced Tony Johnson at Bellator 136 on April 10, 2015.

[18] He lost the fight via unanimous decision marking his second consecutive loss being cut by the Bellator MMA.

[32] Volkov was expected to face Alistair Overeem on April 20, 2019, at UFC Fight Night 149.

[35] However, dos Santos was forced to pull out from the event due to contracting a serious bacterial infection,[36] and he was replaced by Greg Hardy.

[57] With this win, Volkov became the second person in UFC history to finish a fight with an Ezekiel Choke.

[61] However, due to Volkov's knee injury,[62] the bout was moved and took place on December 7, 2024 at UFC 310.

[66][67] Volkov voiced his frustration about one of the judges, Adalaide Byrd, who has had a history of questionable scorecards in both MMA and boxing.

He utilizes his considerable height, long reach, and powerful kicks to deliver accurate strikes from a distance.

[69] In particular, he is known for his patient and technical boxing as well as his punishing body kicks, which he utilized at UFC 254 in his knockout victory against Walt Harris.