| Ryan LaFlare (inactive) | | 7-3-0 | United States | Oct 6, 2018 |
| Daniel Lacerda (inactive) | Miojo | 0-5-0 (1 NC) | Unknown | Feb 24, 2024 |
| Luan Lacerda (inactive) | | 1-3-0 | Brazil | Mar 14, 2026 |
| Aspen Ladd (inactive) | | 4-3-0 | United States | Apr 9, 2022 |
| Noad Lahat (inactive) | Neo | 2-2-0 | Israel | Feb 6, 2016 |
| Tina Lahdemaki (inactive) | Jelly Bean | 0-1-0 | Finland | Jul 16, 2014 |
| Yohan Lainesse (inactive) | White Lion | 1-3-0 | Canada | Jan 20, 2024 |
| Tim Lajcik (inactive) | The Bohemian | 0-2-1 | United States | Sep 22, 2000 |
| Ricardo Lamas (inactive) | The Bully | 11-6-0 | United States | Aug 29, 2020 |
| Jason Lambert (inactive) | The Punisher | 4-4-0 | United States | Sep 6, 2008 |
| Nate Landwehr | The Train | 5-6-0 | United States | Apr 11, 2026 |
| Austen Lane (inactive) | | 1-5-0 (1 NC) | United States | Mar 21, 2026 |
| Lina Lansberg (inactive) | Elbow Queen | 4-7-0 | Sweden | Feb 18, 2023 |
| Taylor Lapilus (inactive) | Double Impact | 6-2-0 | France | Sep 28, 2024 |
| Chad Laprise (inactive) | The Disciple | 6-4-0 | Canada | Dec 8, 2018 |
| Anthony Lapsley (inactive) | The Recipe | 0-2-0 | United States | May 10, 2014 |
| TJ Laramie (inactive) | | 0-2-0 | Canada | Apr 16, 2022 |
| Icho Larenas (inactive) | | 0-1-0 | Canada | Mar 4, 2006 |
| Lorenz Larkin (inactive) | The Monsoon | 5-5-0 | United States | Aug 20, 2016 |
| Jeremy Larsen (inactive) | | 0-3-0 | United States | Oct 19, 2013 |
| Brock Larson (inactive) | | 3-3-0 | United States | Nov 21, 2009 |
| Ilir Latifi (inactive) | The Sledgehammer | 9-7-0 | Albania | May 20, 2023 |
| Sione Latu (inactive) | | 1-0-0 | Unknown | Mar 5, 1999 |
| Jenel Lausa (inactive) | | 1-3-0 | Philippines | Jun 23, 2018 |
| Dan Lauzon (inactive) | The Upgrade | 0-3-0 | United States | May 29, 2010 |
| Joe Lauzon | | 15-12-0 | United States | Oct 18, 2019 |
| Robbie Lawler (inactive) | Ruthless | 15-10-0 | United States | Jul 8, 2023 |
| Tom Lawlor (inactive) | Filthy | 6-5-0 | United States | Mar 5, 2016 |
| Justin Lawrence (inactive) | The American Kidd | 1-2-0 | United States | Apr 13, 2013 |
| Ronnie Lawrence | The Heat | 2-1-0 (1 NC) | United States | Jun 17, 2023 |
| Valmir Lazaro (inactive) | Bidu | 1-2-0 | Brazil | Nov 21, 2015 |
| Zviad Lazishvili (inactive) | | 0-1-0 | Georgia | Oct 23, 2021 |
| Mounir Lazzez (inactive) | The Sniper | 2-2-0 | Tunisia | Jan 21, 2023 |
| Cung Le (inactive) | | 2-2-0 | Vietnam | Aug 23, 2014 |
| Quang Le (inactive) | Bang | 1-3-0 | Vietnam | Sep 13, 2025 |
| Marcus LeVesseur (inactive) | The Prospect | 1-2-0 | United States | Dec 8, 2012 |
| Carlos Leal | The Lion | 2-2-0 | Brazil | Feb 21, 2026 |
| Jordan Leavitt | The Monkey King | 6-4-0 | United States | Jun 6, 2026 |
| Chris Leben (inactive) | The Crippler | 12-10-0 | United States | Dec 28, 2013 |
| Julien Leblanc | | 0-1-0 | Canada | Apr 18, 2026 |
| Jean-Paul Lebosnoyani | Mufasa | 2-0-0 | United States | Jul 18, 2026 |
| Mickael Lebout (inactive) | Ragnar | 1-2-0 | United States | Oct 24, 2015 |
| Justin Ledet (inactive) | El Blanco | 3-4-0 | United States | Oct 31, 2020 |
| Andrea Lee (inactive) | KGB | 5-9-0 | United States | Mar 1, 2025 |
| ChangHo Lee | | 2-1-0 | South Korea | Nov 1, 2025 |
| David Lee (inactive) | | 0-2-0 | United Kingdom | Apr 21, 2007 |
| Jackie Lee (inactive) | | 0-1-0 | Unknown | Feb 7, 1997 |
| James Lee (inactive) | | 0-1-0 | United States | Jan 19, 2008 |
| JeongYeong Lee | Korean Tiger | 2-2-0 | South Korea | May 10, 2025 |
| Kevin Lee | The Motown Phenom | 11-8-0 | United States | Jul 1, 2023 |
| Rocky Lee (inactive) | | 0-1-0 | China | Apr 11, 2015 |
| Vaughan Lee (inactive) | | 3-5-0 | United States | Jul 18, 2015 |
| YiSak Lee | The Tank | 0-1-0 | South Korea | May 30, 2026 |
| Thales Leites (inactive) | | 13-8-0 | Brazil | Sep 22, 2018 |
| Jovan Leka | | 1-0-0 | Serbia | Aug 1, 2026 |
| Amanda Lemos | | 9-7-0 | Brazil | Aug 8, 2026 |
| Christophe Leninger (inactive) | | 0-2-0 | Unknown | May 30, 1997 |
| Jesse Lennox (inactive) | The Ox | 1-2-0 | United States | Jun 12, 2010 |
| Nik Lentz (inactive) | The Carny | 14-9-1 (1 NC) | Unknown | Jan 23, 2021 |
| Alberta Cerra Leon (inactive) | | 0-1-0 | United States | Mar 11, 1994 |
| Victoria Leonardo (inactive) | Fury | 1-4-0 | United States | Aug 24, 2024 |
| Kimo Leopoldo (inactive) | | 2-4-0 | United States | Jun 19, 2004 |
| Brock Lesnar (inactive) | | 4-3-0 (1 NC) | United States | Jul 9, 2016 |
| Frank Lester (inactive) | | 0-1-0 | United States | Jun 20, 2009 |
| Valerie Letourneau (inactive) | Trouble | 3-3-0 | Canada | Dec 10, 2016 |
| Leah Letson (inactive) | Nidas | 1-1-0 | United States | Nov 13, 2021 |
| Justin Levens (inactive) | The Executioner | 0-2-0 | United States | Jun 28, 2006 |
| David Levicki (inactive) | | 0-1-0 | United States | Mar 11, 1994 |
| Natan Levy | Lethal | 2-2-0 | Israel | Mar 16, 2024 |
| Bevon Lewis (inactive) | | 1-3-0 | United States | Nov 7, 2020 |
| Derrick Lewis | The Black Beast | 20-12-0 | United States | Jun 14, 2026 |
| John Lewis (inactive) | | 1-1-0 | Unknown | Nov 17, 2000 |
| Jess Liaudin (inactive) | The Joker | 2-3-0 | France | Oct 18, 2008 |
| Chuck Liddell (inactive) | The Iceman | 16-7-0 | Unknown | Jun 12, 2010 |
| Zach Light (inactive) | | 0-1-0 | United States | Jun 22, 2002 |
| Chris Liguori (inactive) | | 0-1-0 | Unknown | Nov 21, 2003 |
| Hyun Gyu Lim (inactive) | The Ace | 3-4-0 | South Korea | Sep 22, 2017 |
| Andre Lima | Mascote | 5-1-0 | Brazil | Aug 29, 2026 |
| Dhiego Lima (inactive) | | 4-7-0 | United States | Jun 19, 2021 |
| Felipe Lima | Jungle Boy | 3-1-0 | Brazil | Sep 5, 2026 |
| Juliana Lima (inactive) | Ju Thai | 3-4-0 | Brazil | Jan 27, 2018 |
| Marcos Rogerio de Lima (inactive) | Pezao | 11-7-0 | Brazil | Feb 17, 2024 |
| Rodrigo de Lima (inactive) | Monstro | 0-2-0 | Brazil | Feb 14, 2015 |
| Matt Lindland (inactive) | The Law | 9-3-0 | United States | Aug 20, 2005 |
| Jake Lindsey (inactive) | The Librarian | 0-3-0 | United States | Mar 14, 2015 |
| John Lineker (inactive) | Hands of Stone | 12-4-0 | Brazil | Apr 27, 2019 |
| Austin Lingo | Lights Out | 2-3-0 | United States | Jul 15, 2023 |
| Lucio Linhares (inactive) | | 0-2-0 | Brazil | Mar 31, 2010 |
| Philipe Lins | Monstro | 4-2-0 | Brazil | Mar 9, 2024 |
| Zhang Lipeng (inactive) | The Warrior | 2-2-0 | United States | May 16, 2015 |
| Tainara Lisboa | Thai Panther | 2-2-0 | Brazil | Oct 18, 2025 |
| Dean Lister (inactive) | The Boogeyman | 4-2-0 | United States | Dec 27, 2008 |
| Pingyuan Liu (inactive) | | 2-2-0 | China | Dec 21, 2019 |
| James Llontop (inactive) | Goku | 0-3-0 | Peru | Nov 16, 2024 |
| Abner Lloveras (inactive) | Skullman | 0-1-0 | Spain | Dec 11, 2015 |
| John Lober (inactive) | The Machine | 0-1-0 | United States | Oct 16, 1998 |
| Artem Lobov (inactive) | The Russian Hammer | 2-5-0 | Russia | Oct 27, 2018 |
| Ryan Loder | Man of Steel | 1-2-0 | United States | Nov 22, 2025 |
| David Loiseau (inactive) | The Crow | 4-5-0 | Canada | Jun 12, 2010 |
| Hector Lombard (inactive) | | 3-8-0 (1 NC) | Australia | Sep 22, 2018 |
| Xiao Long | | 1-4-0 | China | Aug 29, 2026 |
| Loma Lookboonmee | | 7-4-0 | Thailand | May 30, 2026 |
| Ange Loosa (inactive) | The Last Ninja | 2-3-0 (1 NC) | Congo - Kinshasa | Jun 14, 2025 |
| Bruno Lopes (inactive) | The Brazilian Cowboy | 1-3-0 | Brazil | Aug 8, 2026 |
| Diego Lopes | | 7-3-0 | Brazil | Jun 14, 2026 |
| Dileno Lopes (inactive) | | 0-2-0 | Brazil | Jul 7, 2016 |
| Benito Lopez (inactive) | Golden Boy | 2-2-0 | United States | Nov 5, 2022 |
| Gustavo Lopez (inactive) | | 1-2-1 | United States | Sep 18, 2021 |
| Jorge Lopez (inactive) | | 0-2-0 | United States | May 15, 2012 |
| Matthew Lopez (inactive) | | 2-4-0 | United States | Dec 8, 2018 |
| Steve Lopez (inactive) | | 0-2-0 | United States | Sep 25, 2010 |
| Brendan Loughnane (inactive) | | 0-1-0 | Unknown | Dec 14, 2012 |
| Caolan Loughran (inactive) | The Don | 2-2-0 | Ireland | Mar 22, 2025 |
| Nate Loughran (inactive) | | 1-1-0 | United States | Dec 10, 2008 |
| Ian Loveland (inactive) | The Barn Owl | 1-2-0 | United States | Aug 27, 2011 |
| Waylon Lowe (inactive) | | 2-2-0 | United States | Mar 26, 2011 |
| Robert Lucarelli (inactive) | | 0-1-0 | United States | Mar 11, 1994 |
| Matt Lucas (inactive) | Luke Duke | 0-1-0 | United States | Nov 12, 2011 |
| Stephanie Luciano | Rondinha | 3-1-0 | Brazil | Aug 1, 2026 |
| Iasmin Lucindo | | 5-2-0 | Brazil | Aug 9, 2025 |
| Duane Ludwig (inactive) | Bang | 4-5-0 | United States | Sep 29, 2012 |
| Lawrence Lui | Lok Yin | 1-1-0 | Hong Kong SAR China | Aug 29, 2026 |
| Mike Lullo (inactive) | | 0-2-0 | United States | Sep 17, 2011 |
| Santiago Luna | BorderBoy | 2-1-0 | United States | Jun 6, 2026 |
| Dalcha Lungiambula (inactive) | Champion | 2-5-0 | Congo - Kinshasa | Dec 10, 2022 |
| Vicente Luque | The Silent Assassin | 17-9-0 | United States | Aug 15, 2026 |
| Thaddeus Luster (inactive) | | 0-1-0 | United States | Mar 11, 1994 |
| Travis Lutter (inactive) | The Serial Killer | 2-4-0 | United States | Apr 19, 2008 |
| Tucker Lutz | Top Gun | 1-3-0 | United States | Jul 15, 2023 |
| Stevie Lynch (inactive) | | 0-1-0 | Unknown | Jun 16, 2007 |
| Chris Lytle (inactive) | Lights Out | 10-10-0 | United States | Aug 14, 2011 |