| Edward Faaloloto (inactive) | | 0-2-0 | United States | Nov 5, 2011 |
| Urijah Faber (inactive) | The California Kid | 11-7-0 | United States | Dec 14, 2019 |
| Melinda Fabian (inactive) | | 0-1-1 | Hungary | Jun 23, 2018 |
| Bartosz Fabinski (inactive) | The Butcher | 3-3-0 | Poland | Apr 17, 2021 |
| Ron Faircloth (inactive) | | 0-0-0 (1 NC) | United States | Oct 7, 2005 |
| Jason Fairn (inactive) | | 0-1-0 | Canada | Dec 16, 1994 |
| Zarah Fairn | Infinite | 0-4-0 | France | Sep 2, 2023 |
| Rinat Fakhretdinov (inactive) | Gladiator | 6-0-1 | Russia | Sep 6, 2025 |
| Maiquel Falcao (inactive) | Big Rig | 1-0-0 | Brazil | Nov 20, 2010 |
| Pedro Falcao (inactive) | Pedrinho | 0-2-0 | Brazil | Apr 5, 2025 |
| Dom Mar Fan | Street Buddha | 1-1-0 | Australia | May 2, 2026 |
| Brodie Farber (inactive) | | 0-2-0 | United States | Dec 10, 2008 |
| Kalindra Faria (inactive) | | 0-3-0 | Brazil | Aug 25, 2018 |
| Kelly Faszholz (inactive) | | 0-2-0 | United States | Oct 1, 2016 |
| Paul Felder (inactive) | The Irish Dragon | 9-6-0 | United States | Nov 14, 2020 |
| Carlos Felipe (inactive) | Boi | 3-2-0 | Brazil | Oct 16, 2021 |
| Josh Ferguson (inactive) | Taz | 0-2-0 | United States | Jul 11, 2012 |
| Kevin Ferguson (inactive) | Kimbo Slice | 1-1-0 | Unknown | May 8, 2010 |
| Tony Ferguson (inactive) | El Cucuy | 15-9-0 | United States | Aug 3, 2024 |
| CJ Fernandes (inactive) | | 0-0-1 | United States | Sep 22, 2000 |
| Gabriella Fernandes | Gabi | 3-3-0 | Brazil | Mar 28, 2026 |
| Kaue Fernandes | | 3-2-0 | Brazil | Aug 15, 2026 |
| Luke Fernandez | | 0-1-0 | United States | Mar 7, 2026 |
| Lucas Fernando | | 1-0-0 | Brazil | Aug 15, 2026 |
| Alexandre Ferreira (inactive) | Cacareco | 0-1-0 | United States | Nov 13, 2010 |
| Brunno Ferreira | The Hulk | 6-5-0 | Brazil | Sep 19, 2026 |
| Cezar Ferreira (inactive) | Mutante | 9-6-0 | Brazil | Jul 13, 2019 |
| Diego Ferreira | | 11-7-0 | Brazil | Aug 8, 2026 |
| Scott Ferrozzo (inactive) | The Pitbull | 3-2-0 | United States | Feb 7, 1997 |
| Andre Fialho | | 2-5-0 | Portugal | Sep 23, 2023 |
| Drew Fickett (inactive) | The Master | 4-3-0 | United States | Apr 5, 2007 |
| Scott Fiedler (inactive) | | 0-1-0 | Unknown | Jul 12, 1996 |
| Michal Figlak (inactive) | Mad Dog | 0-2-0 | Poland | Apr 27, 2024 |
| Deiveson Figueiredo | Deus da Guerra | 14-8-1 | Brazil | Oct 3, 2026 |
| Francisco Figueiredo (inactive) | Sniper | 2-2-0 | Brazil | Aug 20, 2022 |
| Edwin Figueroa (inactive) | El Feroz | 2-4-0 | United States | Nov 16, 2013 |
| Jafel Filho | Pastor | 3-3-0 | Brazil | Apr 25, 2026 |
| Andre Fili | Touchy | 13-13-0 (1 NC) | United States | Jun 20, 2026 |
| Mirko Filipovic (inactive) | Cro Cop | 5-6-0 | Unknown | Apr 11, 2015 |
| Torrez Finney | The Punisher | 1-1-0 | United States | Jan 31, 2026 |
| Luigi Fioravanti (inactive) | | 4-5-0 | United States | Feb 7, 2009 |
| Nick Fiore (inactive) | | 0-2-0 | United States | May 20, 2023 |
| Manon Fiorot | The Beast | 8-2-0 | France | Sep 12, 2026 |
| Spencer Fisher (inactive) | The King | 9-8-0 | United States | Jun 22, 2012 |
| Chris Fishgold (inactive) | | 1-3-0 | United Kingdom | Jul 15, 2020 |
| Jon Fitch (inactive) | | 14-3-1 | United States | Feb 2, 2013 |
| Rafael Fiziev | Ataman | 8-5-0 | Kyrgyzstan | Jun 27, 2026 |
| AJ Fletcher | The Ghost | 1-3-0 | United States | Sep 23, 2023 |
| Colin Fletcher (inactive) | The Freakshow | 0-2-0 | United Kingdom | Mar 16, 2013 |
| Nathan Fletcher (inactive) | | 1-2-0 | United Kingdom | Aug 2, 2025 |
| Jimmy Flick (inactive) | The Brick | 2-4-0 | United States | Apr 26, 2025 |
| Kenny Florian (inactive) | KenFlo | 12-5-0 | United States | Oct 8, 2011 |
| Darrius Flowers | Beast Mode | 1-3-0 | United States | Apr 4, 2026 |
| Jason Von Flue (inactive) | Live Wire | 1-2-0 | United States | Aug 17, 2006 |
| Caros Fodor (inactive) | The Future | 0-1-0 | United States | Feb 23, 2013 |
| Rob Font | | 12-9-0 | United States | Mar 7, 2026 |
| Jesse Forbes (inactive) | Kid Hercules | 0-3-0 | United States | May 29, 2010 |
| Jussier Formiga (inactive) | | 9-7-0 | Brazil | Jun 6, 2020 |
| Carol Foro | Anabelle | 1-0-0 | Brazil | Aug 8, 2026 |
| Renee Forte (inactive) | | 1-3-0 | Unknown | Mar 15, 2014 |
| Brianna Fortino (inactive) | The Bull | 1-1-0 | Unknown | Jun 20, 2020 |
| Marcel Fortuna (inactive) | | 1-2-0 | Brazil | Nov 11, 2017 |
| Tyrell Fortune | | 1-1-0 | United States | Jul 25, 2026 |
| Brian Foster (inactive) | The Foster Boy | 3-2-0 | United States | Nov 20, 2010 |
| Xavier Foupa-Pokam (inactive) | Professor X | 0-2-0 | France | May 23, 2009 |
| Hermes Franca (inactive) | | 6-5-0 | Brazil | Sep 19, 2009 |
| Felipe Franco | | 1-1-0 | Brazil | Jul 18, 2026 |
| Rich Franklin (inactive) | Ace | 14-6-0 | United States | Nov 10, 2012 |
| Justin Frazier (inactive) | The Grizzly Bear | 0-1-0 | United States | Nov 30, 2018 |
| Zane Frazier (inactive) | Nasty | 0-1-0 | United States | May 17, 1996 |
| Denzel Freeman | Luke Fox | 1-1-0 | United States | Jan 24, 2026 |
| Ian Freeman (inactive) | The Machine | 3-2-1 | United Kingdom | Jun 6, 2003 |
| Willamy Freire (inactive) | Chiquerim | 0-1-0 | Brazil | Jan 22, 2011 |
| Geraldo de Freitas (inactive) | Spartan | 1-2-0 | Unknown | Nov 14, 2020 |
| Josh Fremd (inactive) | | 2-4-0 | United States | Jul 13, 2024 |
| Matt Frevola | The SteamRolla | 5-6-1 | United States | Oct 18, 2025 |
| Jinh Yu Frey (inactive) | | 2-6-0 | United States | Oct 21, 2023 |
| Philip De Fries (inactive) | | 2-3-0 | United Kingdom | Apr 6, 2013 |
| Sarah Frota (inactive) | A Treta | 0-2-0 | Brazil | Jul 27, 2019 |
| Daniel Frunza | | 0-2-0 | Romania | Nov 1, 2025 |
| Don Frye (inactive) | The Predator | 9-1-0 | United States | Dec 7, 1996 |
| Tony Fryklund (inactive) | The Freak | 2-2-0 | Unknown | Oct 22, 2004 |
| Adam Fugitt (inactive) | | 2-4-0 | United States | Jan 24, 2026 |
| Katsuhisa Fujii (inactive) | Shamoji | 1-1-0 | Unknown | Nov 19, 1999 |
| Riki Fukuda (inactive) | | 2-3-0 | Japan | Mar 2, 2013 |
| Masio Fullen (inactive) | Lobo | 1-2-0 | Mexico | Jan 30, 2016 |
| Sam Fulton (inactive) | | 0-2-0 | United States | Jul 27, 1997 |
| Travis Fulton (inactive) | The Ironman | 1-1-0 | United States | Jul 16, 1999 |
| Ricardo Funch (inactive) | Golden Boy | 0-4-0 | Brazil | Jun 22, 2012 |