| Song Yadong | Kung Fu Kid | 13-4-1 | China | Aug 29, 2026 |
| Jamie Yager (inactive) | The Chosyn 1 | 0-1-0 | United States | Jun 19, 2010 |
| Eddie Yagin (inactive) | The Filipino Phenom | 1-1-0 | United States | Apr 21, 2012 |
| Mohammad Yahya (inactive) | The UAE Warrior | 0-3-0 | United Kingdom | Jul 26, 2025 |
| Rani Yahya | | 13-6-1 (1 NC) | Brazil | Apr 27, 2024 |
| Abdul Rakhman Yakhyaev | The Hunter | 3-0-0 | Russia | Jun 27, 2026 |
| Alexander Yakovlev (inactive) | Russian Thunder | 3-6-0 | Russia | Oct 24, 2020 |
| Keiichiro Yamamiya (inactive) | | 0-1-0 | Japan | Nov 19, 1999 |
| Kenichi Yamamoto (inactive) | | 2-1-0 | Japan | Dec 16, 2000 |
| Norifumi Yamamoto (inactive) | Kid | 0-3-0 (1 NC) | Japan | Feb 28, 2015 |
| Petr Yan | No Mercy | 12-4-0 | Russia | Dec 6, 2025 |
| Wu Yanan (inactive) | Mulan | 1-5-0 | China | Aug 20, 2022 |
| Adam Yandiev (inactive) | Boroda | 0-1-0 | Unknown | Sep 15, 2018 |
| Adrian Yanez | | 7-3-1 | United States | Jul 11, 2026 |
| Dongi Yang (inactive) | The Ox | 2-3-0 | South Korea | Nov 28, 2015 |
| Jianping Yang (inactive) | | 0-1-0 | Unknown | Aug 23, 2014 |
| John Yannis | | 1-2-0 | United States | Jun 6, 2026 |
| Masutatsu Yano (inactive) | | 0-1-0 | Japan | Nov 19, 1999 |
| Hu Yaozong (inactive) | Totoro | 0-3-0 | China | Oct 30, 2021 |
| Emmanuel Yarborough (inactive) | | 0-1-0 | Unknown | Sep 9, 1994 |
| Cale Yarbrough (inactive) | | 0-1-0 | United States | Jul 19, 2008 |
| Yizha | | 1-3-0 | China | Jan 31, 2026 |
| Ashley Yoder | SpiderMonkey | 3-8-0 | United States | Oct 14, 2023 |
| JooSang Yoo | Zombie Jr. | 1-2-0 | South Korea | Sep 19, 2026 |
| Yoshiyuki Yoshida (inactive) | Zenko | 2-3-0 | Japan | May 8, 2010 |
| SuYoung You | Yoo-Jitsu | 3-1-0 | South Korea | Mar 14, 2026 |
| Gauge Young | Gee Money | 2-2-0 | United States | Aug 22, 2026 |
| Jason Young (inactive) | Shotgun | 1-3-0 | United Kingdom | Sep 29, 2012 |
| Shane Young | Smokin' | 2-5-0 | New Zealand | Sep 9, 2023 |
| Shanna Young (inactive) | The Shanimal | 1-3-0 | United States | Nov 5, 2022 |
| Besam Yousef (inactive) | | 0-2-0 | Syria | Apr 6, 2013 |
| Rob Yundt (inactive) | Monster | 0-2-0 | United States | Jun 21, 2008 |
| Sodiq Yusuff | Super | 6-4-0 | Nigeria | May 17, 2025 |
| Gilbert Yvel (inactive) | The Hurricane | 0-3-0 | Unknown | Oct 23, 2010 |