M-1 Global In 2008 Volkov signed with
M-1 Global. His professional MMA debut came in April 2009 when he defeated Nikolay Pleshakov by
TKO in just 80 seconds. Volkov followed this up a month later with another TKO victory, this time against Adam Alikhanov in just 20 seconds. A further month later, Volkov suffered his first professional loss at the hands of Akhmed Sultanov. Midway through the first round, Volkov was forced to tap to an armbar. Volkov then went on a two-fight win streak, both via TKO. Volkov was awarded an M-1 Global ring "as a reward for exceptional performance".
Post M-1 Eastern European Tournament Less than a month later, Volkov took his first fight outside of M-1 in nearly a year. His opponent was the debuting Eldar Yagudin, who he defeated inside the opening round by TKO (punches). In the semifinals at
Bellator 80, he faced
Vinicius Queiroz and won via TKO in the second round. On December 14, Volkov fought
Richard Hale in a 5-round fight for Bellator Season 7 Heavyweight Tournament Final and
Bellator Heavyweight Championship. Volkov won via unanimous decision. In his first title defense, Volkov faced
Vitaly Minakov in the co-main event at
Bellator 108 on November 15, 2013. He lost the bout and his title via TKO in the first round. Volkov faced
Mark Holata on March 7, 2014, at
Bellator 111 in Heavyweight Tournament. He won the fight via TKO in the first round. Volkov faced
Mighty Mo in the semifinals at
Bellator 116 on April 11, 2014. He won the fight via spectacular knockout in the first round. Volkov faced
Blagoy Ivanov in the finals on May 17, 2014, at
Bellator 120. He won the fight via submission in the second round. Nearly a year since his last fight for the promotion, Volkov faced
Tony Johnson at
Bellator 136 on April 10, 2015. He lost the fight via split decision. Volkov faced
Cheick Kongo at
Bellator 139 on June 26, 2015. He lost the fight via unanimous decision marking his second consecutive loss being cut by the Bellator MMA.
Ultimate Fighting Championship In September 2016, it was announced that Volkov has signed with the
Ultimate Fighting Championship. He made his debut against
Timothy Johnson on November 19, 2016, at
UFC Fight Night 99. Volkov was awarded a controversial split decision victory. 12 out of 12 media scores gave the bout to Johnson. Volkov faced
Roy Nelson on April 15, 2017, at
UFC on Fox 24. He won the fight via unanimous decision. Volkov faced
Stefan Struve on September 2, 2017, at
UFC Fight Night: Volkov vs. Struve. He won the bout via TKO in the third round. The win also earned Volkov his first
Fight of the Night bonus award. Volkov faced
Fabrício Werdum on March 17, 2018, at
UFC Fight Night 127. He won the back-and-forth fight via knockout in the fourth round. The win also earned Volkov his first
Performance of the Night bonus award. Volkov weighed in at
UFC 226 on July 6, 2018, serving as the backup for the heavyweight title bout between
Stipe Miocic and
Daniel Cormier. Volkov faced
Derrick Lewis on October 6, 2018, at
UFC 229. Volkov dominated the fight, hurting Lewis multiple times, but ultimately lost the fight via knockout late in round three. Volkov was expected to face
Alistair Overeem on April 20, 2019, at
UFC Fight Night 149. However, on April 3, 2019, it was reported Volkov pulled out from the fight for undisclosed reason. Volkov was scheduled to face
Junior Dos Santos on November 9, 2019, at
UFC on ESPN+ 21. However, dos Santos was forced to pull out from the event due to contracting a serious bacterial infection, and he was replaced by
Greg Hardy. He won the fight via unanimous decision. Volkov faced
Curtis Blaydes on June 20, 2020, at
UFC on ESPN: Blaydes vs. Volkov. Volkov lost the fight by unanimous decision. Volkov faced
Walt Harris on October 24, 2020 at
UFC 254. He won the fight via technical knockout in round two. Volkov faced
Alistair Overeem on February 6, 2021, at
UFC Fight Night 184. He won the fight via technical knockout in round two. This win earned him the
Performance of the Night award. Volkov faced
Ciryl Gane on June 26, 2021, at
UFC Fight Night 190. He lost the fight via unanimous decision. Volkov faced
Marcin Tybura on October 30, 2021, at
UFC 267. He won the bout via unanimous decision. Volkov faced
Tom Aspinall on March 19, 2022, at
UFC Fight Night 204. Volkov lost the fight via straight armbar submission in round one. Volkov faced
Jairzinho Rozenstruik on June 4, 2022, at
UFC Fight Night 207. He won the fight via technical knockout in round one. Volkov faced
Alexander Romanov on March 11, 2023, at
UFC Fight Night 221. He won the fight via technical knockout in the first round. Volkov faced
Tai Tuivasa on September 10, 2023, at
UFC 293. He won the fight with Ezekiel Choke in the second round. With this win, Volkov became the second person in UFC history to finish a fight with an Ezekiel Choke. Volkov faced
Sergei Pavlovich on June 22, 2024, at
UFC on ABC 6. He won the fight by unanimous decision. Volkov was scheduled to face former interim
UFC Heavyweight Champion Ciryl Gane in a rematch on October 26, 2024, at
UFC 308. However, due to Volkov's knee injury, the bout was moved and took place on December 7, 2024, at
UFC 310. Volkov lost the close fight by a controversial, split decision. 19 out of 20 media outlets scored the bout for Volkov. UFC CEO Dana White apologized to Volkov after the bout saying he thought Volkov had won the bout and the head of the commission explained to White what was thought to be the reasoning of the judges' scorecards. Volkov voiced his frustration about one of the judges, Adalaide Byrd, who has had a history of questionable scorecards in both MMA and boxing. Volkov faced
Jailton Almeida on October 25, 2025, at
UFC 321. He won the fight by split decision. Volkov is scheduled to face
Waldo Cortes-Acosta on May 9, 2026, at
UFC 328. ==Fighting style==