| Chris Wade (inactive) | | 5-2-0 | United States | Jul 22, 2017 |
| Neil Wain (inactive) | Old School | 0-1-0 | United Kingdom | Oct 18, 2008 |
| TJ Waldburger (inactive) | | 4-4-0 | United States | Feb 22, 2014 |
| Brogan Walker (inactive) | The Bear | 0-3-0 | United States | Oct 4, 2025 |
| Donny Walker (inactive) | Eagle Eye | 0-2-0 | Unknown | Sep 17, 2011 |
| Johnny Walker | | 9-7-0 (1 NC) | Brazil | Oct 3, 2026 |
| Julius Walker | Juice Box | 1-3-0 | United States | Jun 27, 2026 |
| Valter Walker | The Clean Monster | 5-1-0 | Brazil | Jul 25, 2026 |
| Ben Wall (inactive) | Manimal | 0-2-0 | Australia | May 10, 2014 |
| Crafton Wallace (inactive) | Blaze | 0-2-0 | United States | Oct 10, 2006 |
| Rodney Wallace (inactive) | Shonuff the Master | 0-3-0 | United States | Aug 7, 2010 |
| Jim Wallhead (inactive) | Judo | 0-2-0 | United Kingdom | Jun 3, 2017 |
| Cory Walmsley (inactive) | Hardcore | 0-1-0 | United States | Aug 26, 2006 |
| Patrick Walsh (inactive) | The Beast of the East | 1-1-0 | United States | Feb 14, 2015 |
| Richard Walsh (inactive) | Filthy Rich | 2-4-0 | Australia | Nov 26, 2016 |
| Andy Wang (inactive) | | 0-1-0 | United States | Jun 23, 2007 |
| Anying Wang (inactive) | | 1-1-0 | Unknown | Aug 23, 2014 |
| Sai Wang (inactive) | The Fire Kylin | 1-1-0 | Unknown | Aug 23, 2014 |
| Curt Warburton (inactive) | | 1-2-0 | Unknown | Jun 26, 2011 |
| Charlie Ward (inactive) | | 0-2-0 | Ireland | Jul 16, 2017 |
| Terrion Ware (inactive) | Flash | 0-4-0 | United States | Sep 15, 2018 |
| Ron Waterman (inactive) | H20 | 2-1-1 | United States | Apr 14, 2000 |
| Dominic Waters (inactive) | Sho Nuff | 0-3-0 | United States | May 8, 2016 |
| Trey Waters (inactive) | The Truth | 2-1-0 | United States | Sep 6, 2025 |
| Michelle Waterson-Gomez (inactive) | The Karate Hottie | 6-9-0 | Unknown | Jun 29, 2024 |
| Kyle Watson (inactive) | | 1-1-0 | United States | Apr 30, 2011 |
| Tom Watson (inactive) | Kong | 2-5-0 | United States | Aug 8, 2015 |
| Walel Watson (inactive) | The Gazelle | 1-3-0 | United States | Sep 22, 2012 |
| Brok Weaver (inactive) | Chata Tuska | 1-2-0 | United States | Sep 12, 2020 |
| Jonavin Webb (inactive) | The Spyder | 0-2-0 | United States | Feb 21, 2016 |
| Royston Wee (inactive) | | 2-1-0 | Singapore | May 16, 2015 |
| Darian Weeks (inactive) | | 0-3-0 | United States | Sep 10, 2022 |
| Joshua Weems (inactive) | Wide Open | 0-1-0 | United States | Oct 29, 2022 |
| Chris Weidman (inactive) | The All-American | 12-8-0 | United States | Dec 7, 2024 |
| Zhang Weili | Magnum | 10-3-0 | China | Nov 15, 2025 |
| Mark Weir (inactive) | The Wizard | 1-2-0 | United Kingdom | Apr 25, 2003 |
| Christian Wellisch (inactive) | The Hungarian Nightmare | 2-3-0 | Hungary | Jan 31, 2009 |
| Malcolm Wellmaker | The Machine | 2-2-0 | United States | May 16, 2026 |
| Jeremiah Wells | | 6-2-0 | United States | Aug 15, 2026 |
| Fabricio Werdum (inactive) | Vai Cavalo | 12-6-0 | Brazil | Jul 25, 2020 |
| Mike Wessel (inactive) | Juggernaut | 0-1-0 | United States | Dec 27, 2008 |
| Sheldon Westcott | | 1-2-0 | Canada | Jan 2, 2016 |
| Alex White (inactive) | The Spartan | 4-6-0 | United States | Oct 26, 2019 |
| Craig White (inactive) | The Thundercat | 0-2-0 | United Kingdom | Sep 8, 2018 |
| Vernon White (inactive) | Tiger | 0-1-1 | United States | Aug 21, 2004 |
| Robert Whiteford (inactive) | The Hammer | 2-3-0 | United Kingdom | Apr 10, 2016 |
| Bruce Whitehead | The Goose | 0-1-0 | United States | Oct 3, 2026 |
| Mike Whitehead (inactive) | | 0-1-0 | United States | Feb 4, 2006 |
| Garett Whiteley (inactive) | Goodnight | 0-3-0 | United States | Dec 13, 2014 |
| Emily Whitmire (inactive) | Spitfire | 2-4-0 | United States | Sep 18, 2021 |
| Robert Whittaker | The Reaper | 18-7-0 | Australia | Jul 11, 2026 |
| Adam Wieczorek (inactive) | Siwy | 2-1-0 | Poland | Nov 3, 2018 |
| Orlando Wiet (inactive) | The Gladiator | 1-1-0 | Unknown | Mar 11, 1994 |
| Jonathan Wiezorek (inactive) | | 1-0-0 | United States | Apr 2, 2004 |
| Jakub Wiklacz | | 2-0-0 | Poland | Feb 7, 2026 |
| Aaron Wilkinson (inactive) | The Daywalker | 0-1-0 | United Kingdom | Dec 4, 2010 |
| Mike Wilkinson (inactive) | The Warrior | 2-2-0 | Unknown | Feb 27, 2016 |
| Rob Wilkinson (inactive) | Razor | 0-2-0 | Australia | Feb 10, 2018 |
| James Wilks (inactive) | Lightning | 2-2-0 | United Kingdom | Oct 16, 2010 |
| Cole Williams (inactive) | Havoc | 0-2-0 | United States | Oct 31, 2020 |
| Jordan Williams (inactive) | Bomaye | 0-3-0 | United States | Nov 6, 2021 |
| Karl Williams (inactive) | | 3-1-0 | United States | Aug 10, 2024 |
| Khaos Williams | The OxFighter | 7-5-0 | United States | Oct 3, 2026 |
| Patrick Williams (inactive) | The Animal | 1-3-0 | United States | Apr 14, 2018 |
| Pete Williams (inactive) | El Duro | 3-5-0 | United States | Mar 22, 2002 |
| Tedd Williams (inactive) | | 1-1-0 | United States | Sep 22, 2000 |
| Tim Williams (inactive) | The South Jersey Strangler | 0-2-0 | United States | Aug 25, 2018 |
| Justin Willis (inactive) | Big Pretty | 4-1-0 | United States | Mar 23, 2019 |
| Chris Wilson (inactive) | The Professor | 1-3-0 | United States | Sep 16, 2009 |
| Jonathan Wilson (inactive) | Johnny Bravo | 1-3-0 | United States | Oct 21, 2017 |
| Westin Wilson (inactive) | | 1-3-0 | United States | Aug 23, 2025 |
| Matt Wiman (inactive) | | 10-8-0 | United States | Dec 5, 2020 |
| Eddie Wineland (inactive) | | 6-10-0 | United States | Jun 18, 2022 |
| Deron Winn (inactive) | | 2-3-0 | United States | Jun 18, 2022 |
| Andre Winner (inactive) | | 2-4-0 | United States | Jul 2, 2011 |
| Anthony Wint | Bow Down | 2-0-0 | United States | Oct 3, 2026 |
| Eric Wisely (inactive) | Little Lee | 0-2-0 | United States | Apr 14, 2012 |
| Keith Wisniewski (inactive) | The Polish Connection | 0-4-0 | United States | Sep 4, 2013 |
| Jason Witt (inactive) | The Vanilla Gorilla | 2-4-0 | United States | Aug 13, 2022 |
| Travis Wiuff (inactive) | The Diesel | 0-2-0 | United States | Apr 16, 2005 |
| Ray Wizard (inactive) | | 0-1-0 | United States | Mar 11, 1994 |
| Danyelle Wolf (inactive) | | 0-1-0 | United States | Sep 10, 2022 |
| Brandon Wolff (inactive) | | 0-2-0 | United States | May 23, 2009 |
| Joanne Wood | JoJo | 9-8-0 | United Kingdom | Mar 9, 2024 |
| Nathaniel Wood | The Last Kingsman | 11-4-0 | United Kingdom | Sep 5, 2026 |
| Val Woodburn | The Animal | 0-2-0 | Jamaica | Feb 17, 2024 |
| Tyron Woodley (inactive) | The Chosen One | 9-6-1 | United States | Mar 27, 2021 |
| Sean Woodson | The Sniper | 8-2-1 | United States | Aug 29, 2026 |
| Cal Worsham (inactive) | | 1-2-0 | United States | Dec 7, 1996 |
| Khama Worthy (inactive) | The Death Star | 2-3-0 | United States | Oct 23, 2021 |
| Justin Wren (inactive) | The Viking | 0-1-0 | United States | Dec 5, 2009 |
| Jordan Wright (inactive) | The Beverly Hills Ninja | 2-5-0 | United States | Feb 18, 2023 |
| Marcin Wrzosek (inactive) | The Polish Zombie | 0-1-0 | Unknown | Dec 11, 2015 |
| Wulijiburen (inactive) | Beast Master | 0-3-0 | China | Feb 9, 2019 |