| Alberto Uda (inactive) | | 0-2-0 | Unknown | Aug 20, 2016 |
| Tagir Ulanbekov | | 6-2-0 | Russia | Nov 22, 2025 |
| Carlos Ulberg | Black Jag | 10-1-0 | New Zealand | Apr 11, 2026 |
| Gasan Umalatov (inactive) | Cobra | 1-3-0 | Russia | Nov 7, 2015 |
| Caol Uno (inactive) | Uno Shoten | 3-5-2 | Japan | Mar 31, 2010 |
| Gilbert Urbina | The RGV Bad Boy | 2-3-0 | United States | Aug 1, 2026 |
| Hector Urbina (inactive) | El Toro | 1-2-0 | Mexico | Sep 24, 2016 |
| Yasuhiro Urushitani (inactive) | | 0-2-0 | Japan | Nov 10, 2012 |
| Kamaru Usman | The Nigerian Nightmare | 16-4-0 | Nigeria | Jul 18, 2026 |
| Mohammed Usman (inactive) | The Motor | 4-2-0 | Nigeria | Jun 21, 2025 |
| Darren Uyenoyama (inactive) | BC | 2-2-0 | United States | Dec 14, 2013 |